US says there is evidence of North Korean troops in Russia

The US has said for the first time that it has seen evidence of North Korean troops in Russia, and South Korean lawmakers have said about 3,000 soldiers have been sent to support the Kremlin's war in Ukraine, with more to follow.

The US defence secretary, Lloyd Austin, speaking in Rome, said it would be "very, very serious" if the North Koreans were preparing to fight alongside Russia in Ukraine, as Kyiv has alleged, though he said it remained to be seen what they would be doing there.

"There is evidence that there are DPRK troops in Russia," Austin told reporters, using North Korea's formal name, the Democratic People's Republic of Korea.

In Seoul, South Korean lawmakers said North Korea had sent 3,000 troops to Russia and thousands more were expected to follow.

Pyongyang had promised to provide a total of about 10,000 troops, whose deployment was expected to be completed by December, the lawmakers told reporters after being briefed by South Korea's national intelligence agency.

The figure of 3,000 is twice a previous estimate of numbers of North Korean troops already in Russia.