North Korean troops have engaged in direct combat with Ukrainian forces in Russia's Kursk region, resulting in several casualties, Ukrainian President Volodymyr Zelenskyy said Thursday, CNN reported.

"Eleven thousand North Korean soldiers or soldiers of the North Korean army are currently present on the territory of the Russian Federation in the border with Ukraine on the north of our country in the Kursk region," Zelensky told reporters at the European Political Community summit in Budapest, Hungary.

Early last week, the Pentagon confirmed that North Korea had deployed 10,000 troops to aid Russian President Vladimir Putin in his war against Ukraine. In June, the two countries signed a "comprehensive strategic partnership treaty," which ensures both nations will provide military assistance using "all means" if either is attacked.

"Some of these troops have already taken part in hostilities against the Ukrainian military. Yes, there are already losses. This is a fact," Zelenskyy added without specifying which side had suffered casualties.

Earlier in the week, The New York Times reported that a number of North Korean troops had been killed in a limited engagement, likely to test the Ukrainian line for weakness, senior U.S. and Ukrainian officials said. Ukrainian forces currently hold roughly 250 square miles in the Kursk region following an incursion last summer.

Reports of casualties with North Korean troops come the same week as President-elect Donald Trump defeated Vice President Kamala Harris. Trump has been a vocal critic of supplying Ukraine with aid and has said he will end the war within 24 hours of taking office.

In his evening video address, Zelenskyy said, "I congratulate him on this victory. In general, it was extremely important for us in Ukraine and for all of Europe to consistently hear the words of the then-45th president of the United States about 'peace through strength.'

"And if this becomes the policy principle of the 47th president of the United States, America and the whole world will undoubtedly benefit from it. It is not without reason that Ronald Reagan is mentioned so often these days — people want confidence; they want freedom, a normal life."

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