WASHINGTON — Diplomatic pressure from the United States and Britain, Saudi Arabia’s biggest arms suppliers, abruptly intensified on Wednesday for a cease-fire in the Yemen war, the world’s worst man-made humanitarian disaster.
The calls for a halt to the three-and-a-half-year-old conflict — made by Secretary of State Mike Pompeo, his British counterpart, Jeremy Hunt, and Defense Secretary Jim Mattis — came against the backdrop of rising global criticism of Saudi Arabia, which has led a bombing campaign that is a major cause of civilian deaths and destruction in Yemen, the Arab world’s poorest country.
“It is time to end this conflict, replace conflict with compromise, and allow the Yemeni people to heal through peace and reconstruction,” Mr. Pompeo said in a statement on the State Department website.
The push comes as relations between Saudi Arabia and the United States have cooled in the month since a prominent dissident, Jamal Khashoggi, was killed in Saudi Arabia’s Istanbul consulate by a team of Saudi operatives with close ties to Crown Prince Mohammed bin Salman, Saudi Arabia’s de facto ruler and the architect of the Yemen war.
The Saudi monarchy has denied responsibility for Mr. Khashoggi’s killing in a story that has changed at least five times since he disappeared Oct. 2.
On Wednesday the Istanbul chief prosecutor, in Turkey’s first official account of what happened to Mr. Khashoggi inside the consulate, said that he had been immediately strangled and his body dismembered and destroyed.
President Trump has described the Saudi monarchy’s explanations for what befell Mr. Khashoggi as the world’s “worst cover-up.” But Mr. Trump also has indicated he does not want to punish Saudi Arabia, which is the biggest foreign customer of the American defense industry.
The timing of the call for a Yemen cease-fire and the troubling questions over who was ultimately behind the death of Mr. Khashoggi struck some Middle East analysts as more than a coincidence.
“One of the key things that makes diplomacy work is leverage,” said Dennis Ross, the senior Middle East adviser under President Barack Obama, “and Pompeo has some leverage with the Saudis now that he didn’t have before.”
The Yemen war has killed at least 10,000 people. Repeated efforts by United Nations diplomats to broker a truce between the chief antagonists, a Saudi-led military coalition and Yemen’s Houthi insurgents, have failed.
Mr. Hunt, Britain’s foreign secretary, told the BBC that Mr. Pompeo’s call for a cease-fire was “an extremely welcome announcement.”
Martin Griffiths, the United Nations special envoy for the Yemen conflict, also expressed appreciation. “I urge all concerned parties to seize this opportunity,” Mr. Griffiths said in a statement.
Additional support for a cease-fire came from Mr. Mattis, the United States defense secretary, in an appearance on Tuesday at the United States Institute of Peace, a Washington research group. Mr. Mattis said he believed Saudi Arabia and its principal Arab partner, the United Arab Emirates, were ready for talks that Mr. Griffiths hopes to convene in November.
“We have got to move toward a peace effort here, and we can’t say we are going to do it some time in the future,” Mr. Mattis said.
The United States and Britain have faced increased criticism themselves over their support for the Saudi military in the Yemen war, which includes supplying bombs and intelligence. A growing number of American congressional representatives from both parties have demanded that the United States suspend weapons sales and other aid. Critics of Saudi Arabia in Britain have been pressing Prime Minister Theresa May’s government to do the same.
Although the Saudis say they try to avoid killing civilians in their bombing runs and missile strikes on Houthi targets, their aerial assaults have hit hospitals, markets, school buses and funerals. The Houthis have frequently responded by firing missiles over the border into Saudi Arabia.
The war has led to a staggering humanitarian catastrophe, punctuated by disease, famine and near-famine conditions in parts of the country.
Last week Mark Lowcock, the top humanitarian relief official of the United Nations, said the number of Yemenis who need emergency food to survive could soon reach 14 million, half the population.
The Saudis intervened in Yemen in March 2015 after the Houthis had occupied much of the country and expelled the Saudi-backed government in Sana, the capital. The Saudis contend that the Houthis are supported by Iran, Saudi Arabia’s regional adversary.
For their part, Saudi Arabia and the United Arab Emirates have emphasized they are among the biggest donors to United Nations humanitarian efforts in Yemen. The two countries provided about $930 million, or roughly one third, of the United Nations humanitarian aid budget for Yemen in 2018.
But questions about that aid commitment have arisen over a report that the Saudis and the Emiratis demanded positive publicity from the United Nations relief agency, the Office for the Coordination of Humanitarian Affairs, in return for the support.
The Guardian reported Tuesday that an internal United Nations document showed that the aid from Saudi Arabia and the United Arab Emirates was partly contingent on beneficial publicity about their largess.
Diplomats at the United Nations missions of Saudi Arabia and the United Arab Emirates did not immediately respond to requests for comment on the Guardian report.
Russell Geekie, a spokesman for the Office for the Coordination of Humanitarian Affairs, declined to comment on the report. But he said in an emailed statement that aid agreements with United Nations agencies, sometimes called “visibility plans,” include requirements related to the visibility of the donors.
“All visibility materials that we agree to are used in a manner that is consistent with humanitarian principles of neutrality, impartiality and independence and according to the internal policies of the receiving agencies,” Mr. Geekie said.
The aid provided by Saudi Arabia and the United Arab Emirates, he said, “came with no conditions.”