Russia is seeking surveillance drones from Iran, a top Biden aide says.

WASHINGTON — President Biden’s national security adviser said on Monday that Russia is seeking hundreds of surveillance drones from Iran, including those capable of firing missiles, to use in the war in Ukraine.

The official, Jake Sullivan, said it was unclear whether Iran had already sent any of the remotely piloted systems to Russia, but said that the United States had information that indicated Iran was preparing to train Russian troops to use them as soon as this month.

“Our information indicates that the Iranian government is preparing to provide Russia with up to several hundred U.A.V.s, including weapons-capable U.A.V.s on an expedited timeline,” Mr. Sullivan told reporters at the White House, referring to unmanned aerial vehicles.

Russia’s monthslong bombardment of Ukraine has exhausted Russia of many of its precision-guided weapons, and Mr. Sullivan, in saying that war was “coming at a cost to the sustainment of its own weapons,” seemed to suggest that the Kremlin was, or soon would be, running short on armed surveillance drones.

The timing of Mr. Sullivan’s comments about what presumably had been classified intelligence was also curious, coming almost as an aside at the end of a briefing to preview President Biden’s trip this week to Israel and Saudi Arabia, where Iran’s nuclear program and malign activities in the region will be a key subject of discussion.

Iran has supplied drone and missile technology to Houthi rebels in Yemen, who have attacked Saudi Arabia and the United Arab Emirates, as well as to Shia militia in Iraq, who have carried out drone strikes against U.S. troops there. But Mr. Sullivan’s comments about any imminent transfer of Iranian drones to Russia to use in Ukraine caught several senior U.S. national security officials by surprise on Monday.

The Biden administration is trying to slow Russian weapon manufacturing by denying it components made with Western technology. Gina M. Raimondo, the commerce secretary, said last month that American and international controls had lowered exports to Russia of semiconductors and computer chips by 90 percent.