Tzipi Livni, former Israeli foreign minister poses with a supporter for a selfie, after speaking at a news conference in Tel Aviv, Israel February 18, 2019. REUTERS/Ammar Awad 

Tzipi Livni, former Israeli foreign minister enters a car after speaking at a news conference in Tel Aviv, Israel February 18, 2019. REUTERS/Ammar Awad 

Tzipi Livni, former Israeli foreign minister leaves after speaking at a news conference in Tel Aviv, Israel February 18, 2019. REUTERS/Ammar Awad 

Tzipi Livni, former Israeli foreign minister speaks at a news conference in Tel Aviv, Israel February 18, 2019. REUTERS/Ammar Awad 

Tzipi Livni, former Israeli foreign minister speaks at a news conference in Tel Aviv, Israel February 18, 2019. REUTERS/Ammar Awad 

Former Israeli Foreign Minister Tzipi Livni (L) and Chief Palestinian Negotiator Saeb Erekat participate in the World Economic Forum on the Middle East and North Africa at the King Hussein Convention Centre at the Dead Sea May 20, 2017. REUTERS/Muhammad Hamed 

Former Israeli Foreign Minister Tzipi Livni (L) and Chief Palestinian Negotiator Saeb Erekat participate in the World Economic Forum on the Middle East and North Africa at the King Hussein Convention Centre at the Dead Sea May 20, 2017. REUTERS/Muhammad Hamed 

Former Israeli Foreign Minister Tzipi Livni of the Zionist Union addresses attendees at the "Haaretz Q: with New Israel Fund" event at The Roosevelt Hotel in the Manhattan borough of New York City, December 13, 2015. REUTERS/Andrew Kelly 

Former Israeli Foreign Minister Tzipi Livni of the Zionist Union addresses attendees at the "Haaretz Q: with New Israel Fund" event at The Roosevelt Hotel in the Manhattan borough of New York City, December 13, 2015. REUTERS/Andrew Kelly 

Former Israeli Foreign Minister Tzipi Livni of the Zionist Union addresses attendees at the "Haaretz Q: with New Israel Fund" event at The Roosevelt Hotel in the Manhattan borough of New York City, December 13, 2015. REUTERS/Andrew Kelly 

Former Israeli Foreign Minister Tzipi Livni of the Zionist Union addresses attendees at the "Haaretz Q: with New Israel Fund" event at The Roosevelt Hotel in the Manhattan borough of New York City, December 13, 2015. REUTERS/Andrew Kelly 

Tzipi Livni, co-leader of Zionist Union attends the Most Powerful Women summit in London, Britain June 16, 2015. REUTERS/Stefan Wermuth

Tzipi Livni, co-leader of Zionist Union attends the Most Powerful Women summit in London, Britain June 16, 2015. REUTERS/Stefan Wermuth

Tzipi Livni, co-leader of Zionist Union attends the Most Powerful Women summit in London, Britain June 16, 2015. REUTERS/Stefan Wermuth

Tzipi Livni, co-leader of Zionist Union attends the Most Powerful Women summit in London, Britain June 16, 2015. REUTERS/Stefan Wermuth

Isaac Herzog, co-leader of Zionist Union with Tzipi Livni, delivers a statement at the party headquarters in Tel Aviv March 18, 2015. Israeli Prime Minster Benjamin Netanyahu pledged on Wednesday to form a new governing coalition quickly after an upset election victory that was built on a shift to the right and is likely to worsen a troubled relationship with the White House. With nearly all votes counted on Wednesday, Netanyahu's Likud had won 30 seats in the 120-member Knesset, comfortably defeating the center-left Zionist Union opposition on 24 seats. A united list of Israeli Arab parties came in third.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C) and Tzipi Livni (L), co-leaders of Zionist Union, gesture as they deliver a statement at the party headquarters in Tel Aviv March 18, 2015. Israeli Prime Minster Benjamin Netanyahu pledged on Wednesday to form a new governing coalition quickly after an upset election victory that was built on a shift to the right and is likely to worsen a troubled relationship with the White House. With nearly all votes counted on Wednesday, Netanyahu's Likud had won 30 seats in the 120-member Knesset, comfortably defeating the center-left Zionist Union opposition on 24 seats. A united list of Israeli Arab parties came in third.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS TPX IMAGES OF THE DAY) 

Isaac Herzog (L) and Tzipi Livni, co-leaders of Zionist Union, deliver a statement at the party headquarters in Tel Aviv March 18, 2015. Israeli Prime Minster Benjamin Netanyahu pledged on Wednesday to form a new governing coalition quickly after an upset election victory that was built on a shift to the right and is likely to worsen a troubled relationship with the White House. With nearly all votes counted on Wednesday, Netanyahu's Likud had won 30 seats in the 120-member Knesset, comfortably defeating the center-left Zionist Union opposition on 24 seats. A united list of Israeli Arab parties came in third.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (R) and Tzipi Livni, co-leaders of Zionist Union, raise their arms at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu claimed victory in Israel's election after exit polls showed he had erased his centre-left rivals' lead with a hard rightward shift in which he abandoned a commitment to negotiate a Palestinian state. Herzog, Netanyahu's chief opponent and head of the centre-left Zionist Union, said "everything is still open" and that he already had spoken to party leaders about forming a government. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (7th R) and Tzipi Livni (5th R), co-leaders of Zionist Union, stand with party members at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu claimed victory in Israel's election on Tuesday after exit polls showed he had erased his center-left rivals' lead with a hard rightward shift that saw him disavow a commitment to negotiate a Palestinian state.Difficult coalition talks still lie ahead. Herzog, Netanyahu's chief opponent and head of the center-left Zionist Union, said "everything is still open" and that he had already spoken to party leaders about forming a government. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (R) and Tzipi Livni, co-leaders of Zionist Union, hold up their hands at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu's main challenger, Zionist Union chief Herzog, disputed Netanyahu's victory claim in Israel's election on Tuesday, saying "everything is open". "This result allows us to return to power," Herzog told supporters at party headquarters in Tel Aviv after exit polls showed a tie between the centre-left Zionist Union and Netanyahu's right-wing Likud. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Tzipi Livni (L), co-leader of Zionist Union, is hugged at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu claimed victory in Israel's election on Tuesday after exit polls showed he had erased his center-left rivals' lead with a hard rightward shift that saw him disavow a commitment to negotiate a Palestinian state.Difficult coalition talks still lie ahead. Isaac Herzog, Netanyahu's chief opponent and head of the center-left Zionist Union, said "everything is still open" and that he had already spoken to party leaders about forming a government. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog and Tzipi Livni (3rd R), co-leaders of Zionist Union, hug after addressing supporters at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu's main challenger, Zionist Union chief Herzog, disputed Netanyahu's victory claim in Israel's election on Tuesday, saying "everything is open". "This result allows us to return to power," Herzog told supporters at party headquarters in Tel Aviv after exit polls showed a tie between the centre-left Zionist Union and Netanyahu's right-wing Likud. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (R) and Tzipi Livni, co-leaders of Zionist Union, raise their arms at party headquarters in Tel Aviv March 18, 2015. Prime Minister Benjamin Netanyahu's main challenger, Zionist Union chief Herzog, disputed Netanyahu's victory claim in Israel's election on Tuesday, saying "everything is open". "This result allows us to return to power," Herzog told supporters at party headquarters in Tel Aviv after exit polls showed a tie between the centre-left Zionist Union and Netanyahu's right-wing Likud. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (centre L) and Tzipi Livni (centre R), co-leaders of the center-left Zionist Union party, campaign outside a polling station in Modiin near Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win. If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C) and Tzipi Livni (2nd R), co-leaders of the center-left Zionist Union party, stand outside a polling station while campaigning in Modiin near Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win. If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (centre L) and Tzipi Livni (centre R), co-leaders of the center-left Zionist Union party, campaign outside a polling station in Modiin near Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win. If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C) and Tzipi Livni (2nd R), co-leaders of the center-left Zionist Union party, campaign outside a polling station in Modiin near Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win. If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (L) and Tzipi Livni, co-leaders of the center-left Zionist Union party, speak to the media at party headquarters in Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win. If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Stringer (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (centre L) and Tzipi Livni (centre R), co-leaders of the center-left Zionist Union party, stand outside a polling station while campaigning in Modiin near Tel Aviv March 17, 2015. Prime Minister Benjamin Netanyahu faced a fight for his political survival on Tuesday as Israelis voted in an election that opinion polls predict the centre-left opposition could win.If he narrowly loses the vote, Netanyahu is probably still better placed than the opposition Zionist Union to cobble together a coalition, setting him on track to become Israel's longest-serving prime minister. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (L) speaks with Tzipi Livni, his co-leader of the center-left Zionist Union party, while campaigning outside a polling station in Modiin near Tel Aviv March 17, 2015. Millions of Israelis turned out to vote on Tuesday in a tightly-fought election, with Prime Minister Benjamin Netanyahu facing an uphill battle to defeat a strong campaign by the centre-left opposition to deny him a fourth term in office. When the last opinion polls were published on March 13, the centre-left Zionist Union led by Herzog held a four-seat lead over Netanyahu's Likud, a margin that had the opposition set for a surprise victory. REUTERS/Ronen Zvulun (ISRAEL - Tags: POLITICS ELECTIONS TPX IMAGES OF THE DAY) 

Isaac Herzog (C) and Tzipi Livni (L), co-leaders of the center-left Zionist Union party, speak to the media while campaigning in Tel Aviv March 17, 2015. Millions of Israelis turned out to vote on Tuesday in a tightly-fought election, with Prime Minister Benjamin Netanyahu facing an uphill battle to defeat a strong campaign by the centre-left opposition to deny him a fourth term in office. When the last opinion polls were published on March 13, the centre-left Zionist Union led by Herzog held a four-seat lead over Netanyahu's Likud, a margin that had the opposition set for a surprise victory. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Runners wear masks depicting Naftali Bennett (R), leader of the far-right Jewish Home party, Isaac Herzog (C) and Tzipi Livni, leaders of the centre-left Zionist Union party, after an Election Race organised by a local gym at the Yarkon park in Tel Aviv March 16, 2015. Bennett emerged as a surprise success story in the 2013 election, advocating annexation of more than half of the occupied West Bank and calling a Palestinian state "suicide" for Israel. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

A runner wearing a mask depicting co-leader of the centre-left Zionist Union party Tzipi Livni, sits after an Election Race organised by a local gym at the Yarkon park in Tel Aviv March 16, 2015. Israel's Prime Minister Benjamin Netanyahu, in a final bid to shore up right-wing support ahead of a knife-edge vote on Tuesday, said he would not permit a Palestinian state to be created under his watch if he is re-elected. Herzog favors reviving peace talks with U.S.-backed Palestinian President Mahmoud Abbas. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

A combination picture shows Isaac Herzog (L), co-leader of the centre-left Zionist Union party, briefing the foreign media in Jerusalem, in a file picture taken February 24, 2015, and Israeli Prime Minister Benjamin Netanyahu attending a cabinet meeting in Jerusalem March 8, 2015. Netanyahu, trailing in opinion polls two days before a parliamentary election, on March 15, 2015 implored right-wing voters to turn out and "stop a left-wing government from coming to power." Final opinion polls published on March 13, 2015 predicted the centre-left Zionist Union led by Herzog and Tzipi Livni would take between 24 and 26 seats in Tuesday's vote, compared to 20-22 seats for Likud. REUTERS/Ronen Zvulun/Files (L) and Gali Tibbon/Pool (JERUSALEM - Tags: POLITICS ELECTIONS HEADSHOT) 

Israel's Prime Minister Benjamin Netanyahu (R) and Isaac Herzog, co-leader of the centre-left Zionist Union, are pictured together as campaign billboards rotate in Tel Aviv March 15, 2015. Netanyahu, trailing in opinion polls two days before a parliamentary election, on Sunday implored right-wing voters to turn out and "stop a left-wing government from coming to power." Final opinion polls published on Friday predicted the centre-left Zionist Union led by Herzog and Tzipi Livni would take between 24 and 26 seats in Tuesday's vote, compared to 20-22 seats for Likud. Picture taken March 15, 2015.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Israel's Prime Minister Benjamin Netanyahu, Isaac Herzog and Tzipi Livni are depicted on Likud (R) and Zionist Union (L) campaign billboards in Tel Aviv March 15, 2015. Israel's centre-left opposition is poised for an upset victory in next week's parliamentary election, with the last opinion polls before Tuesday's vote giving it a solid lead over Netanyahu's party. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (front L) and Tzipi Livni (front R), leaders of the centre-left Zionist Union party, speak on the phone with potential voters at their party's headquarters in Tel Aviv March 15, 2015. Israel's centre-left opposition is poised for an upset victory in next week's parliamentary election, with the last opinion polls before Tuesday's vote giving it a solid lead over Prime Minister Benjamin Netanyahu's party. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (L) and Tzipi Livni, leaders of the centre-left Zionist Union party, speak on the phone with potential voters at their party's headquarters in Tel Aviv March 15, 2015. Israel's centre-left opposition is poised for an upset victory in next week's parliamentary election, with the last opinion polls before Tuesday's vote giving it a solid lead over Prime Minister Benjamin Netanyahu's party. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

Supporters of the centre-left Zionist Union party wear t-shirts bearing the names of the party's co-leaders, Isaac Herzog, also known by his nickname, Buji, and Tzipi Livni, during a campaign stop in the southern city of Ashdod, March 13, 2015. Israel's centre-left opposition is poised for an upset victory in national elections next week, with the last opinion polls before the March 17 vote giving it a solid lead over Prime Minister Benjamin Netanyahu's party.
REUTERS/Amir Cohen (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C), co-leader of the centre-left Zionist Union, and party co-leader Tzipi Livni (2nd-R) shake hands with a vendor during a campaign stop at a fruit and vegetable market in Tel Aviv March 12, 2015. Co-leader of the centre-left Zionist Union, Herzog is an Israeli blue blood - a son of a former president, grandson of a renowned rabbi and nephew of one Israel's most notable foreign ministers.A lawyer who has headed the Labour Party since 2013, Herzog, 54, was first elected to parliament in 2003 and has held a series of cabinet posts in various coalitions.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog, (centre L) co-leader of the centre-left Zionist Union, and party co-leader Tzipi Livni (centre R) seen during a campaign stop at a fruit and vegetable market in Tel Aviv March 12, 2015. Co-leader of the centre-left Zionist Union, Herzog is an Israeli blue blood - a son of a former president, grandson of a renowned rabbi and nephew of one Israel's most notable foreign ministers.A lawyer who has headed the Labour Party since 2013, Herzog, 54, was first elected to parliament in 2003 and has held a series of cabinet posts in various coalitions.
REUTERS/Baz Ratner(ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C), co-leader of the centre-left Zionist Union, and party co-leader Tzipi Livni (R) seen during a campaign stop at a fruit and vegetable market in Tel Aviv March 12, 2015. Co-leader of the centre-left Zionist Union, Herzog is an Israeli blue blood - a son of a former president, grandson of a renowned rabbi and nephew of one Israel's most notable foreign ministers.A lawyer who has headed the Labour Party since 2013, Herzog, 54, was first elected to parliament in 2003 and has held a series of cabinet posts in various coalitions.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C) co-leader of the centre-left Zionist Union and party co-leader Tzipi Livni (2nd-R), drink during a campaign stop at a fruit and vegetable market in Tel Aviv March 12, 2015. Co-leader of the centre-left Zionist Union, Herzog is an Israeli blue blood - a son of a former president, grandson of a renowned rabbi and nephew of one Israel's most notable foreign ministers.A lawyer who has headed the Labour Party since 2013, Herzog, 54, was first elected to parliament in 2003 and has held a series of cabinet posts in various coalitions.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog (C) co-leader of the centre-left Zionist Union and party co-leader Tzipi Livni (2nd-R), seen during a campaign stop at a fruit and vegetable market in Tel Aviv March 12, 2015. Co-leader of the centre-left Zionist Union, Herzog is an Israeli blue blood - a son of a former president, grandson of a renowned rabbi and nephew of one Israel's most notable foreign ministers.A lawyer who has headed the Labour Party since 2013, Herzog, 54, was first elected to parliament in 2003 and has held a series of cabinet posts in various coalitions.
REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

A man works near an election campaign poster depicting Tzipi Livni and Isaac Herzog, heads of the centrist Zionist Union party, at the party's headquarters in Tel Aviv March 11, 2015. Israelis will vote in a parliamentary election on March 17, choosing among party lists of candidates to serve in the 120-seat Knesset. Currently, polls show Israeli Prime Minister Netanyahu's Likud party and the centre-left Zionist Union opposition running neck-and-neck, with each predicted to win around 24 seats in the Knesset. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

A man walks past election campaign posters depicting Tzipi Livni and Isaac Herzog, heads of the centrist Zionist Union party, at the party's headquarters in Tel Aviv March 11, 2015. Israelis will vote in a parliamentary election on March 17, choosing among party lists of candidates to serve in the 120-seat Knesset. Currently, polls show Israeli Prime Minister Netanyahu's Likud party and the centre-left Zionist Union opposition running neck-and-neck, with each predicted to win around 24 seats in the Knesset. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

Election campaign posters depicting Tzipi Livni and Isaac Herzog, heads of the centrist Zionist Union party, are seen at the entrance
to the party's headquarters in Tel Aviv March 11, 2015. Israelis will vote in a parliamentary election on March 17, choosing among party lists of candidates to serve in the 120-seat Knesset. Currently, polls show Israeli Prime Minister Netanyahu's Likud party and the centre-left Zionist Union opposition running neck-and-neck, with each predicted to win around 24 seats in the Knesset. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

Election campaign posters depicting Tzipi Livni and Isaac Herzog, heads of the centrist Zionist Union party, are seen at the party's headquarters in Tel Aviv March 11, 2015. Israelis will vote in a parliamentary election on March 17, choosing among party lists of candidates to serve in the 120-seat Knesset. Currently, polls show Israeli Prime Minister Netanyahu's Likud party and the centre-left Zionist Union opposition running neck-and-neck, with each predicted to win around 24 seats in the Knesset. REUTERS/Nir Elias (ISRAEL - Tags: POLITICS ELECTIONS) 

Workers cut freshly printed campaign posters in Arabic, that depict Isaac Herzog (top L), who heads the centre-left Zionist Union with former cabinet minister Tzipi Livni, and Zehava Galon (bottom 2nd L), chair of the left-wing Meretz party, at a print shop in the Arab Israeli town of Baqa al-Gharbiya, March 2, 2015. A political sideshow for much of the past six decades, Israel's Arab minority is hoping to gain much-needed muscle after next week's parliamentary election, with four Arab parties uniting under one banner for the first time. Arab voter turnout in the 2013 election was 57 percent, lower than the 68 percent national average. Arab citizens make up about 15 percent of eligible voters, which means they have an electoral potential of 18 seats. Picture taken March 2, 2015. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS) 

Isaac Herzog, head of the centrist Zionist Union party, holds a news conference with party co-leader Tzipi Livni (silhouetted behind him) in Tel Aviv to introduce the party's platform for the March 17 election, March 8, 2015. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Tzipi Livni (R) and Isaac Herzog, heads of the centrist Zionist Union party, hold a news conference in Tel Aviv to introduce their party's platform for the March 17 election, March 8, 2015. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Tzipi Livni (R) and Isaac Herzog, heads of the centrist Zionist Union party, hold a news conference in Tel Aviv to introduce their party's platform for the March 17 election, March 8, 2015. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Tzipi Livni (L) and Isaac Herzog, heads of the centrist Zionist Union party, hold their party's platform for the March 17 election during a news conference in Tel Aviv March 8, 2015. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Tzipi Livni (R) and Isaac Herzog, heads of the centrist Zionist Union party, hold a news conference in Tel Aviv to introduce their party's platform for the March 17 election, March 8, 2015. REUTERS/Baz Ratner (ISRAEL - Tags: POLITICS ELECTIONS) 

Workers hold freshly printed campaign banners in Arabic that depict Isaac Herzog (L), who heads the centre-left Zionist Union alliance with former cabinet minister Tzipi Livni, and Zehava Galon (R), chair of the left-wing Meretz party, at a printing factory in the Arab village of Baqa al-Gharbiya in northern Israel March 2, 2015. Opinions polls show a tight race ahead of the March 17 election, campaigning for which has been dominated by economic issues like high living costs and workers wages. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS) 

A worker cuts a freshly printed campaign placard in Arabic that depicts Isaac Herzog (L), who heads the centre-left Zionist Union alliance with former cabinet minister Tzipi Livni, at a printing factory in the Arab village of Baqa al-Gharbiya in northern Israel March 2, 2015. Opinions polls show a tight race ahead of the March 17 election, campaigning for which has been dominated by economic issues like high living costs and workers wages. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS) 

A worker cuts freshly printed campaign banners in Arabic that depict Isaac Herzog (L), who heads the centre-left Zionist Union alliance with former cabinet minister Tzipi Livni, and Zehava Galon (top right), chair of the left-wing Meretz party, at a printing factory in the Arab village of Baqa al-Gharbiya in northern Israel March 2, 2015. Opinions polls show a tight race ahead of the March 17 election, campaigning for which has been dominated by economic issues like high living costs and workers wages. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS) 

A worker cuts freshly printed campaign banners in Arabic that depict Isaac Herzog (L), who heads the centre-left Zionist Union alliance with former cabinet minister Tzipi Livni, and Zehava Galon (top right), chair of the left-wing Meretz party, at a printing factory in the Arab village of Baqa al-Gharbiya in northern Israel March 2, 2015. Opinions polls show a tight race ahead of the March 17 election, campaigning for which has been dominated by economic issues like high living costs and workers wages. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS) 

Former cabinet minister Tzipi Livni (R) of the center-left Zionist Union coalition attends a conference to address the Israeli Arab public ahead of the general election that will be held March 17, in the Israeli-Arab city of Shfaram in northern Israel February 28, 2015. REUTERS/Ammar Awad (ISRAEL - Tags: POLITICS ELECTIONS)