U.N. Pushes to Avert ‘Catastrophic’ U.A.E. Attack on Yemen Port

WASHINGTON—The United Nations launched an urgent diplomatic effort to head off an expected United Arab Emirates assault on Yemen’s most important port in the coming days, fearing an attack could create a humanitarian disaster and derail the most promising push in years to end the conflict, people familiar with the talks said.

Aid groups and U.N. officials working in the Red Sea port city of Hodeidah are scrambling to get their international staff out after British officials warned them an attack on the city was imminent.

The U.N. special envoy for Yemen, Martin Griffiths, traveled to the U.A.E. capital over the weekend in an effort to forestall an attack. Mr. Griffiths had secured an agreement with Houthi rebels who control Hodeidah to allow the U.N. to operate the port jointly, the people said. But people briefed on the discussions said they doubted the U.A.E. would accept the offer or delay the planned assault.

Saudi Arabia has accused Iran of using Hodeidah to smuggle missiles into Yemen—a charge Tehran rejects. The U.A.E.—Saudi Arabia’s most important ally in a military coalition fighting in Yemen—has a significant military presence near the port, where it is supporting Yemeni allies in their push to seize Hodeidah from the Houthi fighters.

U.N. officials have said an attack on the port, the gateway for 80% of commercial and humanitarian supplies for the country, could be devastating to a country where millions of people are on the brink of famine.