The United States said on Thursday that up to 8,000 North Korean troops had reached Russia’s border region with Ukraine ready for combat, after Pyongyang’s firing of a long-range missile ramped up tensions days before the US election.

Seeking advantage in his grinding invasion of Ukraine, President Vladimir Putin has brought in troops from North Korea, the first time Russia has invited foreign forces on its soil in more than a century.

Citing US intelligence, Secretary of State Antony Blinken said that some 8,000 of the 10,000 North Korean troops believed to be in Russia have made their way to the Kursk border region.

“We’ve not yet seen these troops deploy into combat against Ukrainian forces, but we would expect that to happen in the coming days,” Blinken told a news conference after four-way talks with the South Korean foreign and defence ministers.

Russia has been training North Korean troops in artillery, drones, basic artillery operations and trench clearing, “indicating that they fully intend to use these forces in frontline operations,” Blinken said.

Defence Secretary Lloyd Austin said that North Korean troops were being supplied with Russian uniforms.

“Make no mistake, if these North Korean troops engage in combat or combat support operations against Ukraine, they would make themselves legitimate military targets,” Austin said. The United States was also preparing a new package of military support to Ukraine in light of the North Korean troops’ arrival, he added.

Ukraine outrage

Ukrainian President Volodymyr Zelensky, speaking to South Korean media, denounced “inaction by allies and said he was surprised by the `silence’ of China on North Korean troop deployment.

“I think that the reaction to this is nothing; it has been zero,” Zelensky said.

South Korea has said it is reviewing whether to send weapons directly to Ukraine in response, an idea it has previously resisted due to longstanding domestic policy that prevents it from sending weaponry into active conflicts.

North Korea’s missile launch “seems to have been carried out to divert attention from international criticism of its troop deployment”, said Yang Moo-jin, president of the University of North Korean Studies in Seoul.