President Joe Biden’s administration has allowed Ukraine to use U.S.-made weapons to strike deep into Russia, two U.S. officials and a source familiar with the decision said on Sunday, in a significant reversal of Washington’s policy in the Ukraine-Russia conflict, writes Reuters.

Ukraine plans to conduct its first long-range attacks in the coming days, the sources said, without revealing details due to operational security concerns.

The move comes two months before President-elect Donald Trump takes office on Jan. 20 and follows months of pleas by Ukrainian President Volodymyr Zelensky to allow Ukraine’s military to use U.S. weapons to hit Russian military targets far from its border.

The change comes largely in response to Russia’s deployment of North Korean ground troops to supplement its own forces, a development that has caused alarm in Washington and Kyiv, a U.S. official and a source familiar with the decision said.

Zelensky said in his evening address that the missiles would “speak for themselves”: “Today, many in the media are saying that we have received permission to take appropriate actions. But strikes are not made with words. Such things are not announced”.

The White House and U.S. State Department declined to comment. There was no immediate response from the Kremlin, which has warned that it would see a move to loosen the limits on Ukraine’s use of U.S. weapons as a major escalation.