An arms-embargo provision of that resolution requires all member states to “take the necessary measures to prevent the direct or indirect supply, sale or transfer to” designated Yemeni combatants including the Houthis.
Saudi Arabia and the United States have long accused Iran of arming the Houthis in Yemen, the Arab world’s most impoverished country. Iran has rejected the accusations and countered that the Saudi-led bombing campaign in Yemen is largely responsible for the humanitarian catastrophe that has unfolded there.
More than 10,000 people have been killed in the Yemen conflict, millions have been displaced and are at risk of acute hunger and malnutrition and one million have been infected with cholera.
A Saudi-imposed embargo on Yemen has only recently been eased, in part because of a humanitarian outcry by the United Nations and other groups.
There was no immediate comment from Iran on the United Nations report, which was prepared by experts for a Council panel responsible for monitoring compliance with the arms embargo.
The report came nearly a month after Nikki R. Haley, the American ambassador to the United Nations, showed reporters a display of recovered war debris, including missile pieces and drone fragments, that she described as proof of Iranian complicity in arming the Houthis.
Ms. Haley’s presentation was greeted at the time with some skepticism, and Iranian officials dismissed it as propaganda.
Whether the United Nations panel’s findings will lead to a shift in opinion against Iran and possible punitive action by the Security Council is unclear.
But news of the findings came as the Trump administration has ramped up pressure on Iran over a range of concerns, most notably the 2015 nuclear deal between Iran and big powers including the United States.
While President Trump stopped short on Friday of reimposing sanctions that could upend the nuclear deal, he warned European allies that he would reimpose them in four months if the accord, intended to stop Iran from developing nuclear arms, was not strengthened.
Mr. Trump also authorized sanctions on 14 Iranian individuals and entities that the United States holds responsible for the repression of anti-government protests that erupted a few weeks ago.