WASHINGTON >> The United States said on Monday it was Russia that is escalating the conflict in Ukraine by deploying North Korean troops, after the Kremlin warned that Washington would deepen its involvement in the war by allowing Kyiv’s forces to strike far into Russia with U.S.-made weapons.

State Department spokesperson Matthew Miller in a briefing declined to confirm that the outgoing administration of President Joe Biden had decided to allow the strikes, but reiterated that the U.S. “will always adapt and adjust the capabilities we provide to Ukraine when it’s appropriate to do so.”

Reuters reported on Sunday that the Biden administration has decided to allow Ukraine to conduct the strikes, a move U.S. officials speaking on condition of anonymity said was a response to the presence of North Korean troops in the conflict.

Kremlin spokesman Dmitry Peskov said on Monday that the outgoing administration was adding fuel to the fire and seeking to escalate the conflict in Ukraine.

Russia’s U.N. Ambassador Vassily Nebenzia told a Security Council meeting on Monday, citing media reports, that the Biden administration had issued “suicidal permissions to Zelenskiy to use long-range weapons to strike inside Russia.”

“Perhaps Joe Biden, for many reasons, has nothing left to lose, but we are astounded by the short-sightedness of the leadership of UK and France,” he said.

“They are eager to play into the hands of the exiting administration and are dragging not just their countries, but the entire Europe into a large-scale escalation with drastic consequences,” Nebenzia added.

Miller earlier on Monday said it was Russia that has repeatedly escalated the conflict, pointing to the 11,000 North Korean troops the U.S. says have been deployed and have clashed with Ukrainian forces in Russia’s Kursk region.

“That is a major escalation by Russia bringing in an Asian military to a conflict inside Europe,” Miller said, adding that the U.S. response would be firm. “We will continue to do what is appropriate to hold Russia accountable for its actions, including its escalatory actions, and to hold North Korea accountable for its escalatory actions.”

British Foreign Secretary David Lammy told reporters at the United Nations that the presence of North Korean troops was a “major, major escalation,” and pledged to put Ukraine in the strongest possible position.