Russia's presidential office spokesperson has declined to comment on a US government report that 10,000 North Korean troops have arrived in the Kursk region, where Ukraine's military is conducting cross-border attacks.

Dmitry Peskov was asked by a reporter on Tuesday whether he could confirm or comment on a statement made by US State Department Spokesperson Matthew Miller the previous day.

Miller said that the department had assessed that as many as 10,000 North Korean troops have made their way to Kursk. He added they could "enter combat in the coming days."

Peskov said he would not comment on the matter because every US official who talks about it adds that the US side does not have final confirmation.

In late October, Russian President Vladimir Putin did not deny reports that North Korean troops were dispatched to his country when he was asked about it at a news conference.

Meanwhile, Russia launched a missile attack on the southern Ukrainian city of Zaporizhzhia on Tuesday. The local governor said six people were killed and 24 others were injured. Key infrastructure facilities were also reportedly damaged.

Ukrainian presidential office head Andriy Yermak said on social media that the violence must be stopped by strong action. He added that a stronger position of the allies is needed.