A man collects Yemeni riyal banknotes at the Houthi-run Central Bank of Yemen in Sanaa, Yemen June 30, 2021. Picture taken June 30, 2021. REUTERS/Nusaibah Almuaalemi

A man receives bands of Yemeni riyal banknotes at the Houthi-run Central Bank of Yemen in Sanaa, Yemen June 30, 2021. Picture taken June 30, 2021. REUTERS/Nusaibah Almuaalemi

A cashier counts Yemeni riyal banknotes at a local currency exchange in Aden, Yemen June 29, 2021. Picture taken June 29, 2021. REUTERS/Fawaz Salman

Yemeni riyal banknotes are pictured at a local currency exchange in Aden, Yemen June 29, 2021. Picture taken June 29, 2021. REUTERS/Fawaz Salman

Yemeni currency banknotes are counted on a counting machine at an exchange company in Sanaa, Yemen June 28, 2021. Picture taken June 28, 2021. REUTERS/Nusaibah Amluaalemi

Yemeni singer, Fouad al-Kebsi and his brother Akram, sit with guests for the iftar meal at their family house during the holy month of Ramadan in Sanaa, Yemen April 19, 2021. Picture taken April 19, 2021. REUTERS/Khaled Abdullah

A Yemeni government fighter fires a vehicle-mounted weapon at a frontline position during fighting against Houthi fighters in Marib, Yemen March 28, 2021. Picture taken March 28, 2021. REUTERS/Ali Owidha

A Yemeni government fighter fires a vehicle-mounted weapon at a frontline position during fighting against Houthi fighters in Marib, Yemen March 28, 2021. Picture taken March 28, 2021. REUTERS/Ali Owidha

A Yemeni government fighter fires a vehicle-mounted weapon at a frontline position during fighting against Houthi fighters in Marib, Yemen March 9, 2021. Picture taken March 9, 2021. REUTERS/Ali Owidha

A Yemeni government fighter holds a machine gun bullet belt at a frontline position during fighting against Houthi fighters in Marib, Yemen March 16, 2021. Picture taken March 16, 2021. REUTERS/Ali Owidha

A Yemeni government fighter fires a vehicle-mounted weapon at a frontline position during fighting against Houthi fighters in Marib, Yemen March 9, 2021. Picture taken March 9, 2021. REUTERS/Ali Owidha TPX IMAGES OF THE DAY

A man walks with his son as they buy a lantern ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

People shop in a mall ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10, 2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A boy sells jackets on a street ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A man looks on as he sells dates ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A man looks at diary products as he shops ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A woman buys traditional bead accessories as she shops ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A boy pushes a shopping cart with his brother during preparations for the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

A man shops ahead of the holy fasting month of Ramadan, in Sanaa, Yemen, April 10,2021. Picture taken April 10, 2021. REUTERS/Nusaibah Almuaalemi

Smoke and dust rise near buildings from air strikes launched by Saudi-led coalition on Sanaa, Yemen March 7, 2021. REUTERS/Khaled Abdullah

Smoke and dust rise near buildings from what a Reuters witness and residents said was air strikes launched by Saudi-led coalition on Sanaa, in Yemen March 7, 2021. REUTERS/Khaled Abdullah

People assist an injured person outside Madina Hospital after a blast Luul Yemeni restaurant near the port in Mogadishu, Somalia March 5, 2021. REUTERS/Feisal Omar

An injured civilian stands outside Madina Hospital after a blast at the Luul Yemeni restaurant near the port in Mogadishu, Somalia March 5, 2021. REUTERS/Feisal Omar

People assist an injured person outside Madina Hospital after a blast at the Luul Yemeni restaurant near the port in Mogadishu, Somalia March 5, 2021. REUTERS/Feisal Omar

Yemeni ministers attend the first meeting of their cabinet, a day after they survived an attack on Aden airport, in Aden, Yemen December 31, 2020. REUTERS/Fawaz Salman

Yemeni Prime Minister Maeen Abdulmalik addresses the first meeting of his cabinet, a day after he and the ministers survived an attack on Aden airport, in Aden, Yemen December 31, 2020. REUTERS/Fawaz Salman

Yemeni ministers pray as they attend the first meeting of their cabinet, a day after they survived an attack on Aden airport, in Aden, Yemen December 31, 2020. REUTERS/Fawaz Salman

Yemeni government officials speak to a man injured in an attack on Aden airport, at a hospital in Aden, Yemen December 31, 2020. REUTERS/Fawaz Salman

Yemeni government officials speak to a man injured in an attack on Aden airport, at a hospital in Aden, Yemen December 31, 2020. REUTERS/Fawaz Salman

Yemeni government officials, including Foreign Minister Ahmed bin Mubarak, speak to each other at Aden airport after explosions hit the airport upon the arrival of a newly formed cabinet for government-held parts of Yemen, at the airport in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

People react after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

People react after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

People walk on the tarmac as dust and smoke rise after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

A military vehicle is seen on the tarmac as dust rises after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

People react as dust rises after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman TPX IMAGES OF THE DAY

A security personnel member reacts as dust rises after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman

Dust rises after explosions hit Aden airport, upon the arrival of the newly-formed Yemeni government in Aden, Yemen December 30, 2020. REUTERS/Fawaz Salman TPX IMAGES OF THE DAY

A Saudi officer walks with an army officer of Yemen's separatist Southern Transitional Council (STC) are pictured during the redeployment of STC forces from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Military personnel of Yemen's separatist Southern Transitional Council are pictured during their redeployment from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Military personnel of Yemen's separatist Southern Transitional Council are pictured during their redeployment from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Saudi military personnel are pictured with members of Yemen's separatist Southern Transitional Council (STC) forces during the redeployment of STC forces from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Military personnel of Yemen's separatist Southern Transitional Council are pictured during their redeployment from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Military personnel of Yemen's separatist Southern Transitional Council are pictured during their redeployment from the southern Yemeni province of Abyan, Yemen December 14, 2020. REUTERS/Adam Muhammad

Artist Ahlam Nasser paints on a plate using coffee at her home in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Artist Ahlam Nasser paints on a plate using coffee at her home in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Artist Ahlam Nasser paints on a plate using coffee at her home in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Artist Ahlam Nasser paints on a plate using coffee at her home in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Pieces painted by artist Ahlam Nasser are seen on a wall at her home yard in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Pieces painted by artist Ahlam Nasser are seen on a wall at her home in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

Artist Ahlam Nasser explains pieces she painted at her home yard in Sanaa, Yemen November 23, 2020. Picture taken November 23, 2020. REUTERS/Khaled Abdullah

A view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Nael Shyoukhi

A view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Nael Shyoukhi

The debris are seen at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Nael Shyoukhi

An employee is seen in front of the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Nael Shyoukhi

A general view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Marwa Rashad

A general view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Marwa Rashad

A member of the staff stands next to the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Marwa Rashad

A view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Nael Shyoukhi

A general view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Marwa Rashad

A general view shows the damage at a Saudi Aramco oil company distribution station that Yemeni Houthis say they attacked, in the city of Jeddah, Saudi Arabia, November 24, 2020. REUTERS/Marwa Rashad