"We're going to reprioritize the deliveries of these exports so that those missiles rolling off the production line will now be provided to Ukraine," particularly Patriot and NASAMS missiles, National Security Council spokesman John Kirby told journalists.

"Deliveries of these missiles to other countries that are currently in the queue will have to be delayed," he said.

Kirby said that deliveries to Taiwan -- which is preparing for a possible invasion by China -- and Israel, which faced a large-scale missile and drone attack by Iran earlier this year and is fighting a war against Hamas -- will not be affected by the decision.

The United States has been a key military backer of Ukraine, committing more than $51 billion in weapons, ammunition and other security assistance since Russia launched its full-scale invasion in February 2022.