Russia has received ballistic missiles from Iran for its war in Ukraine, the United States said on Tuesday as it imposed fresh sanctions on ships and companies it said were involved in supplying Moscow with Iranian weapons.

At a news conference in London ahead of a visit to Kyiv that Britain's Foreign Secretary David Lammy and he will make, Secretary of State Antony Blinken said Washington had privately warned Iran that providing ballistic missiles to Russia would be "a dramatic escalation."

"Russia has now received shipments with these ballistic missiles, and will likely use them within weeks in Ukraine, against Ukraine," Blinken said, citing intelligence that he said has been shared with U.S. allies and partners around the world.