The United Nations says 5,700 people have been killed in the conflict in Yemen since March 26, including 830 women and children.

The U.N.'s humanitarian coordinator for Yemen, Johannes Van Der Klaauw, told reporters Wednesday that 21.2 million people, or 82 percent of the country's population, require some kind of humanitarian assistance.

He says Yemen's basic services are collapsing and that 14 million people lack sufficient access to health care.

In addition, 1.8 million children have been out of school since the conflict began.

A Saudi-led coalition backing the internationally recognized government has been fighting Iran-backed Houthi rebels.

The conflict has severely hurt efforts to get aid to many places around Yemen, which even before the conflict was the Arab world's poorest nation.