Ukrainian President Volodymyr Zelensky on Monday said that he expects 12,000 North Korean soldiers on Russian territory "soon", as he met with Nordic leaders in Iceland.
As Zelensky made his first visit to Iceland amid a diplomatic push to rally allies around his "victory plan", he warned that some 3,000 North Korean soldiers and officers were "already on Russian territory".
Russia "will use" them in its war on Ukraine, he added.
"We think that they will have 12,000 soon" on Russian territory, Zelensky said at a press conference on Monday evening held together with leaders from the Nordic countries.
Earlier on Monday, the United States said that North Korea has sent some 10,000 troops to train in Russia, more than tripling the previous estimate as NATO warned of a dangerous expansion of the Ukraine war.
Zelensky arrived in Iceland on Monday to attend the fourth Ukraine-Nordic Summit and hold talks with leaders from Denmark, Finland, Iceland, Norway and Sweden.
Asked about the risks of declining military and financial support from the US if the Republican candidate Donald Trump would win the upcoming presidential election, Zelensky said he "hadn't heard" Trump say he would withdraw support.
"Not supporting Ukraine would be a great victory for (Russian President Vladimir) Putin and a great loss for the West, for unity, democracy and freedom", he added.