WASHINGTON — The Biden administration is accusing Russia of moving to provide advanced military assistance to Iran, including air defense systems, helicopters and fighter jets, part of deepening cooperation between the two nations as Tehran provides drones to support President Vladimir Putin’s invasion of Ukraine.

White House National Security Council spokesman John Kirby on Friday cited U.S. intelligence assessments for the allegations, saying Russia was offering Iran “an unprecedented level of military and technical support that is transforming their relationship into a full-fledged defense partnership.”

Kirby said Russia and Iran were considering starting up a drone assembly line in Russia for the Ukraine conflict, while Russia was training Iranian pilots on the Sukhoi Su-35 fighter and Iran could receive deliveries of the plane within the year.

The U.S. allegations are part of a deliberate effort by the U.S. to drive global isolation of Russia, in this case targeted at Arab nations who have looked to contain Iran’s regional malevolence and who have not taken a strong stance against Russia’s invasion of Ukraine.

Kirby said the arms transfers were in violation of U.N. Security Council resolutions and that the U.S. would be “using the tools at our disposal to expose and disrupt these activities.”

The administration says Iran sold hundreds of attack drones to Russia over the summer.

Kirby on Friday reiterated the administration’s belief that Iran is considering the sale of hundreds of ballistic missiles to Russia, but acknowledged that the U.S. doesn’t have “perfect visibility into Iranian thinking on why” the deal hasn’t been consummated.