The training period before North Korean soldiers join the fight in Vladimir Putin’s invasion has been cut short, Kyiv says.

North Korean troops were expected to undergo a month’s training, Ukrainian defence minister Rustem Umerov said, but that “is now being shortened to… two weeks or one week so that they could get engagement in the battlefield”.

North Korean personnel will finish deploying within a few weeks once they complete training in the Russian Far East, experts have said.

A total of 15,000 troops could be deployed along northeastern, eastern and southeastern parts of the 1,000km (600-mile) frontline in Ukraine, according to Mr Umerov.

Russia has declined to acknowledge that North Korean troops are operating in its territory, but Putin last week did not deny reports of their presence. He said it was up to Russia how to implement its defence pact with Pyongyang.

President Volodymyr Zelensky said the first battles between the Ukrainian military and North Korean troops “open a new page in instability in the world” after his defence minister said a “small engagement” had taken place.

Mr Zelensky, in his nightly video address, thanked those in the world who, he said, had reacted to the dispatch of North Korean troops to Russia last month “not just with words … but who are preparing actions to support our defence”.

“The first battles with North Korean soldiers open a new page of instability in the world,” he said.

He said that Ukraine, acting with the rest of the world, had to “do everything so that this Russian step to expand the war with real escalation fails.”

Ukrainian defence minister Rustem Umerov confirmed in an interview with South Korean television that the first engagement had occurred with North Korean troops, an escalation in a conflict that began when Russia invaded Ukraine in 2022.

Ukrainian forces have engaged in “small-scale” clashes with North Korean troops in Kursk, Ukraine’s defence minister Rustem Umerov said.

“Yes, I think so. It is (an) engagement,” Mr Umerov told South Korea’s KBS television in an interview broadcast yesterday, when asked if a clash had occurred.

The report quoted Mr Umerov as saying that the engagement was small for now, but more are expected as the number of North Koreans deployed grows.

“(There are) already contacts, but after a couple of weeks, we would see a more significant number and upon this, we will review it and analyse it,” he said.

Mr Umerov said the Russian military was trying to pass off the North Korean soldiers as Buryats, a Mongolian ethnic group from Siberia, making their identification more challenging for Kyiv.