U.S. Capitol police officers gather prior to a ceremony honoring fellow officer William Evans, who was killed on April 2 and will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Carlos Barria/Pool

A Bentley car is being offloaded outside the Windsor castle, after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in Windsor, near London, Britain April 13, 2021. REUTERS/Matthew Childs

U.S. Capitol police officers gather prior to a ceremony honoring fellow officer William Evans, who was killed on April 2 and will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Carlos Barria/Pool

A Bentley car drives to the Windsor castle, after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in Windsor, near London, Britain April 13, 2021. REUTERS/Matthew Childs

A grey heron is seen at the Sempione park, after Lombardy was downgraded from a red to an orange zone, loosening the coronavirus disease (COVID-19) restrictions including allowing non-essential shops to re-open, in Milan, Italy, April 13, 2021. REUTERS/Flavio Lo Scalzo

A Muslim wearing face mask as precaution against the coronavirus disease (COVID-19), attends Ramadan Tarawih prayers at Sultan Mosque in Singapore, April 13, 2021. REUTERS/Edgar Su

A man waits at the beginning of a trial against 12 Germans charged with belonging to a far-right organisation, that prosecutors say aimed to carry out attacks against politicians, asylum seekers and Muslims, at a higher regional court in Stuttgart, Germany, April 13, 2021. Pool via REUTERS

A man stands with his face covered at the beginning of a trial against 12 Germans charged with belonging to a far-right organisation, that prosecutors say aimed to carry out attacks against politicians, asylum seekers and Muslims, at a higher regional court in Stuttgart, Germany, April 13, 2021. Pool via REUTERS

Muslims wearing face masks as precaution against the coronavirus disease (COVID-19), attend Ramadan Tarawih prayers at Sultan Mosque in Singapore, April 13, 2021. REUTERS/Edgar Su

Muslims keeping social distance as precaution against the coronavirus disease (COVID-19), attend Ramadan Tarawih prayers at Sultan Mosque in Singapore, April 13, 2021. REUTERS/Edgar Su

Muslims wearing face masks as precaution against the coronavirus disease (COVID-19), attend Ramadan Tarawih prayers at Sultan Mosque in Singapore, April 13, 2021. REUTERS/Edgar Su

A guardsman walks outside the Buckingham Palace after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in London, Britain April 13, 2021. REUTERS/John Sibley

A U.S. Capitol police officer stands outside the U.S. Capitol prior to a ceremony honoring fellow officer William Evans, who was killed on April 2 and will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Carlos Barria/Pool

U.S. Capitol police officers gather prior to a ceremony honoring fellow officer William Evans, who was killed on April 2 and will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Carlos Barria/Pool

U.S. Capitol police officers gather prior to a ceremony honoring fellow officer William Evans, who was killed on April 2 and will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Carlos Barria/Pool

People take photos of flowers and tributes to Britain's Prince Philip, husband of Queen Elizabeth, outside the Buckingham Palace in London, Britain April 13, 2021. REUTERS/John Sibley

A man receives a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares to use AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A woman receives a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A woman receives a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares to use AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

People wait to receive AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares to use AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares to use AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A man receives a dose of the AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

People wait after receiving the first dose of he AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

Syringes with AstraZeneca coronavirus disease (COVID-19) vaccines are prepared in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A woman receives a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A nurse prepares to use AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

People wait to receive a dose of AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

A couple talks with a doctor before receiving AstraZeneca coronavirus disease (COVID-19) vaccine in Fasano Italy, April 13, 2021. REUTERS/Alessandro Garofalo REFILE - CORRECTING YEAR

People sit outside the entrance to the Buckingham Palace after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in London, Britain April 13, 2021. REUTERS/John Sibley

Police members attempt to disperse journalists at the state news agency, demonstrating against a new chief executive whose appointment they see as an attempt to undermine editorial independence, in Tunis, Tunisia April 13, 2021. REUTERS/Tarek Amara

Police members stand guard at Tunis Afrique Presse's (TAP) headquarters in Tunis, Tunisia April 13, 2021. REUTERS/Tarek Amara

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas with Russia's Aslan Karatsev after winning their second round match REUTERS/Eric Gaillard

A tribute to Britain's Prince Philip, husband of Queen Elizabeth, is attached to the fencing outside the Buckingham Palace in London, Britain April 13, 2021. REUTERS/John Sibley

A man walks in front of the board showing the graph of the German share price index DAX at the stock exchange in Frankfurt, Germany, April 13, 2021. REUTERS/Staff

The U.S. flag at the U.S. Capitol is flown at half-staff prior to a ceremony honoring late U.S. Capitol Police officer William Evans, who will lie in honor in the Capitol rotunda in Washington, U.S., April 13, 2021. REUTERS/Joshua Roberts

The U.S. flag is flown at half-staff prior to a ceremony honoring late U.S. Capitol Police officer William Evans, who will lie in honor in the rotunda at the U.S. Capitol in Washington, U.S., April 13, 2021. REUTERS/Joshua Roberts

Snipers of the Ukrainian armed forces aim their rifles during training at a firing range near the town of Marinka in Donetsk region, Ukraine April 13, 2021. REUTERS/Anastasia Vlasova

The U.S. flag is flown at half-staff prior to a ceremony honoring late U.S. Capitol Police officer William Evans, who will lie in honor in the rotunda at the U.S. Capitol in Washington, U.S., April 13, 2021. REUTERS/Joshua Roberts

A sniper of the Ukrainian armed forces fires his rifle during training at a firing range near the town of Marinka in Donetsk region, Ukraine April 13, 2021. REUTERS/Anastasia Vlasova

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas in action during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

Empty tables are seen at a closed restaurant amid the coronavirus disease (COVID-19) pandemic at the Baltic Sea resort Timmendorfer Strand, Germany April 13, 2021. REUTERS/Fabian Bimmer

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas in action during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Russia's Aslan Karatsev in action during his second round match against Greece's Stefanos Tsitsipas REUTERS/Eric Gaillard

A note is seen among flowers outside Windsor castle, after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in Windsor, near London, Britain April 13, 2021. REUTERS/Phil Noble

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas in action during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas in action during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

A man gestures in front of a police officer, as workers protest at Rome's Circo Massimo calling on the government to set a date when they can reopen their business, in Rome, Italy, April 13, 2021. REUTERS/Yara Nardi

A person receives a dose of the Johnson & Johnson coronavirus disease (COVID-19) vaccine during a visit of U.S. Vice President Kamala Harris to a vaccination center in Chinatown, in Chicago, Illinois, U.S., April 6, 2021. Picture taken April 6, 2021. REUTERS/Carlos Barria

A medical worker prepares a syringe with a dose of the Johnson & Johnson coronavirus disease (COVID-19) vaccine during a visit of U.S. Vice President Kamala Harris to a vaccination center in Chinatown, in Chicago, Illinois, U.S., April 6, 2021. Picture taken April 6, 2021. REUTERS/Carlos Barria

A healthcare worker takes a swab sample from an Ultra-Orthodox Jewish man for the coronavirus disease (COVID-19) test, after returning from overseas, at Ben Gurion International Airport in Lod, near Tel Aviv, Israel April 13, 2021. REUTERS/Ronen Zvulun

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas in action during his second round match against Russia's Stefanos Tsitsipas REUTERS/Eric Gaillard

Tennis - ATP Masters 1000 - Monte Carlo Masters - Monte-Carlo Country Club, Roquebrune-Cap-Martin, France - April 13, 2021 Greece's Stefanos Tsitsipas reacts during his second round match against Russia's Aslan Karatsev REUTERS/Eric Gaillard

A note is seen among flowers outside Windsor castle, after Britain's Prince Philip, husband of Queen Elizabeth, died at the age of 99, in Windsor, near London, Britain April 13, 2021. REUTERS/Phil Noble

North Rhine-Westphalia's State Premier and head of Germany's conservative Christian Democratic Union (CDU) party Armin Laschet arrives before a CDU/CSU fraction meeting in Berlin, Germany April 13, 2021. REUTERS/Annegret Hilse

Framed pictures of Britain's Prince Philip, husband of Queen Elizabeth, who died at the age of 99, are seen among flowers outside Windsor castle, near London, Britain April 13, 2021. REUTERS/Phil Noble