UNITED NATIONS — The United States on Tuesday sponsored a United Nations Security Council session intended to draw attention to the dire consequences of the war in Yemen, but the meeting also raised questions about potential crimes committed by a Saudi-led military offensive that the Pentagon actively supports.

The United States refuels military jets and provides intelligence support to the military coalition, led by Saudi Arabia, that is trying to defeat Houthi insurgents in Yemen. Since those airstrikes began in March, more than 2,700 civilians have been killed, dozens of schools and hospitals have been attacked and the United Nations has warned of breaches of international law.

But during the session on Tuesday, the United Nations’ top human rights official said that the Saudi-led coalition bore the greatest responsibility for the civilian carnage. The official, Zeid Ra’ad al-Hussein, the high commissioner for human rights, said that while both sides in the conflict had engaged in attacks on civilians, “a disproportionate amount appeared to be the result of airstrikes carried out by coalition forces.”

The United Nations deputy emergency relief chief, Kyung-wha Kang, also warned of the suffering inflicted on civilians by the war, pointing out that two million Yemenis were malnourished and that the country’s health system “is close to collapse.”