AP
In this Thursday, Feb. 1, 2018 photograph, a Yemeni man stands in front of a truck carrying relief materials from Saudi Arabia at a camp for those displaced by Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, a Saudi soldier guards an aid flight at an air base in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, Saudi airmen prepare an aid flight for Yemen in Riyadh, Saudi Arabia. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, Saudi pilots fly a relief flight heading from Saudi Arabia to Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, a Saudi airman takes a break while on a relief flight heading from Saudi Arabia to Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Saturday, Feb. 3, 2018 photograph, relief workers unload aid carried into Yemen by the Saudi military in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, Yemenis needing aid listen to a relief worker from Saudi Arabia at a camp for those displaced by Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Saturday, Feb. 3, 2018 photograph, Abdullah al-Wadei, the assistant director of medical and environmental assistance at the King Salman Humanitarian Aid and Relief Center, races children at a camp for those displaced by Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Saturday, Feb. 3, 2018 photograph, a relief worker signals a forklift driver unloading aid carried into Yemen by the Saudi military in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Saturday, Feb. 3, 2018 photograph, a Yemeni child holds a Yemeni riyal note worth $2 handed out by Saudi officials at a camp from those fleeing violence in Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, an armed Yemeni soldier walks behind another man praying at a camp for those displaced by Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, a young boy talks to an armed Yemeni soldier at a camp for those displaced by Yemen's war in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell
In this Thursday, Feb. 1, 2018 photograph, a young Yemeni boy living in a camp for people displaced by his country's war holds a box of aid from Saudi Arabia in Marib, Yemen. Saudi Arabia, which is at war with the Shiite rebels who hold Yemen's capital, is also delivering aid to the Arab world's poorest country. (AP Photo/Jon Gambrell)
- Jon Gambrell