US to impose new sanctions on Iran over support for Russia: White House

The United States will soon impose new sanctions on Iran over its backing for Russia's invasion of Ukraine, the White House said Thursday.

"In response to Iran's ongoing support for Russia's brutal war, we will be imposing additional sanctions on Iran in the coming days, and we are prepared to go further if Iran sells ballistic missiles to Russia," National Security Council spokesman John Kirby told journalists.

"Iran is not helping Russia for free. In return for Iran's support, Russia has been offering Tehran unprecedented defense cooperation. So in total Iran is seeking billions of dollars' worth of military equipment from Russia," Kirby said.

Ukrainian forces are running short of ammunition as they fight against invading Russian troops, with additional funding for Kyiv held up in the US Congress.

Moscow has turned to Tehran as well as Pyongyang to obtain arms for use in Ukraine, while Russia has also massively ramped up its domestic arms production.