Malcolm Chalmers, deputy director-general of the Royal United Services Institute military think tank, told CBS News in March that about 20% of Ukraine's military hardware is supplied by the U.S., with 25% provided by Europe and the rest of the world, and 55% produced in Ukraine.

The Kremlin has repeatedly said arms shipments to Ukraine from allies prolong the conflict Moscow started and raise the risk of escalation. The U.S. confirmed this week it had paused supplying some arms to fight Russian aggression.

The Trump administration is pausing some weapons shipments to Ukraine, including air defense missiles, following a review of military spending and American support to foreign countries, a senior White House official told CNN.