North Korean troops are poised to be deployed by Russia on the battlefield in Ukraine as early as this weekend, Ukrainian President Volodymyr Zelenskyy claimed Friday.

Western officials have warned that such a development would stoke the almost three-year war and bring geopolitical consequences as far away as the Indo-Pacific region.

Zelenskyy said Ukrainian intelligence had determined that “the first North Korean military will be used by Russia in combat zones” between Sunday and Monday.

He said on Telegram that the deployment was “an obvious escalating move by Russia.” He didn’t provide any further details, including where the North Korean soldiers may be sent.

Russia has been conducting a ferocious summer campaign along the eastern front in Ukraine, gradually compelling Kyiv to give up ground. But Russia has struggled to push Ukrainian forces out of its Kursk border region following an incursion almost three months ago.

The deployment of North Korean forces under a military pact between Moscow and Pyongyang brings a new dimension to the conflict, which is Europe’s biggest war since World War II and has cost tens of thousands of lives on both sides, including many civilians.

The US said Wednesday that 3,000 North Korean troops have been deployed to Russia and are training at several locations, calling the move very serious.

Zelenskyy said a week ago that his government has intelligence information that 10,000 troops from North Korea are being readied to join Russian forces fighting against his country. He said that a third nation wading into the hostilities would turn the conflict into a “world war.”

North Korea had already been supplying ammunition to Russia under a defence pact, but putting boots on the ground could complicate a war that has divided international politics, with most Western countries supporting Kyiv.

Russian President Vladimir Putin, meanwhile, has looked for support among BRICS countries.