North Korean troops in Russia might 'soon' join fray in Ukraine: Pentagon

The United States expects that thousands of North Korean troops massing in Russia will "soon" enter combat against Ukraine, Pentagon chief Lloyd Austin has said.

About 10,000 North Korean soldiers were believed to be based in the Russian border region of Kursk, Austin said on Saturday, where they were being "integrated into the Russian formations".

"Based upon what they've been trained on, the way they've been integrated into the Russian formations, I fully expect to see them engaged in combat soon," Austin told reporters during a stopover in Pacific nation Fiji.

Austin said he had "not seen significant reporting" of North Korean troops being "actively engaged in combat" to date.

South Korean government officials and a research group on Thursday said Russia has provided Pyongyang with oil, anti-air missiles and economic help in exchange for the troops Washington and Seoul have accused it of sending.

Kiev has claimed that Moscow, alongside the North Korean soldiers, has now amassed a 50,000-strong force to wrest back parts of the border region seized by Ukrainian forces.

Ukraine claimed swathes of Kursk in August during a lightning offensive even as its troops were thinly stretched in the Donetsk region, which has borne the brunt of nearly three years of fighting.

US military drills with South Korea and Japan

Meanwhile, North Korea has condemned a recent joint military drills by the United States, South Korea and Japan, warning that it would take immediate actions if needed to defend the state.

Last week, the three countries held a three-day joint exercise, dubbed "Freedom Edge", featuring fighter jets and marine patrol aircraft as well as the U.S. nuclear-powered aircraft carrier, USS George Washington.

"We strongly warn the US and its followers hostile towards the DPRK to immediately st op the hostile acts of further causing provocation and instability that can drive the military confrontation in the Korean peninsula and its vicinity into a real armed conflict," the North's Defence Ministry said, using the country's official name.

The military would keep all options available and take immediate actions if needed to preemptively control risk, while closely watching military activity by the US and its allies, it said in a statement carried by state media KCNA.