China slammed the U.S. for "pouring fuel on fire and escalating the war" for allowing Kyiv to use the missile system, which has a range of up to 190 miles.

Vladimir Putin has warned that allowing U.S. weapons to strike inside Russia would make America a direct party to the conflict.

The Kremlin said on Monday that any U.S. decision to allow Ukraine to fire American missiles deep into Russia would mean it was directly involved in the conflict, which it accused President Joe Biden's administration of escalating.