WATCH: ‘Relatively small numbers’ of North Korean troops in Russia’s Kursk region, Pentagon’s Ryder says

BRUSSELS (AP) – North Korea has sent about 10,000 troops to Russia to train and likely fight against Ukraine within “the next few weeks,” the Pentagon said Monday, in a move that Western leaders say will intensify the nearly three-year war and conflict conditions in the Indo-Pacific region.

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Western leaders say North Korea has sent about 10,000 troops to help Russia’s military campaign and warn that its involvement in a European war could also upset relations in the Indo-Pacific region, including Japan and Australia.

Zelenskyy said he spoke with South Korean President Yoon Suk Yeol and told him that 3,000 North Korean troops are already at military bases close to the Ukrainian front line and that he expects the deployment to rise to 12,000.

READ MORE: North Korea’s foreign minister visits Russia as its troops train to fight in Ukraine

At the Pentagon on Tuesday, spokesman Maj. Gen. Pat Ryder said a “relatively small number” of North Korean troops are now in Russia’s Kursk region, where Russian troops have been fighting to push back a Ukrainian incursion, and a few thousand more are headed in that direction .

South Korea, which has been in close contact with NATO, the US and the EU on recent developments, warned last week that it could send weapons to Ukraine in retaliation for the North’s involvement.

“There is only one conclusion – this war is internationalized and goes beyond the borders of Ukraine and Russia,” Zelenskyy wrote on Telegram.

The Ukrainian president also said he and Yoon agreed to intensify their countries’ cooperation and exchange more intelligence, as well as develop concrete responses to Pyongyang’s involvement.

In Washington, White House national security adviser Jake Sullivan met with Zelenskyy’s top adviser on Tuesday to discuss the North Korean troops as well as an upcoming wave of weapons that the United States is supplying to Kiev to help the Ukrainians harden protection of their energy infrastructure. according to White House officials familiar with their private conversations.

Sullivan and Andriy Yermak, head of the Ukrainian president’s office, shared concerns that North Korean troops could be deployed to Russia’s Kursk region and what such a development could mean for the conflict.

The officials, who were not authorized to comment publicly, said during the two-hour meeting at the White House that Sullivan also briefed Yermak on President Joe Biden’s plans to push additional artillery systems, ammunition, hundreds of armored vehicles and more to Ukraine, before he leaves office in January.

READ MORE: What would North Korean troops in Russia mean for the war with Ukraine?

Sullivan told Yermak that by the end of the year, the U.S. government plans to supply Ukraine with 500 additional Patriot and ARAAM missiles to help bolster its air defenses, according to the officials.

Meanwhile, North Korea said its top diplomat is visiting Russia in another sign of their deepening relationship.

Tensions on the Korean Peninsula are at their highest point in years, with North Korea continuing a series of provocative weapons tests and South Korea and the United States expanding their military exercises.

Russian drones, missiles and bombs smashed into Kiev and Kharkiv, Ukraine’s largest cities, in overnight attacks, killing four people and wounding 15 in a sustained airstrike, authorities said on Tuesday.

Russia has bombed civilian areas in Ukraine almost daily since its full-scale invasion of its neighbor, causing thousands of casualties.

The Russian army is also pressing hard on frontline defenses in the eastern Donetsk region of Ukraine. The Russian Defense Ministry claimed on Tuesday that Russian troops captured the Donetsk city of Hirnyk and the villages of Katerynivka and Bohoiavlenka.

Zelenskyy also spoke about the war at a meeting on Tuesday in Reykjavik with the leaders of Denmark, Iceland, Finland, Norway and Sweden. He said a conference will begin in Canada on Wednesday to discuss the abduction of what he said were tens of thousands of children by Russia from the occupied territories of Ukraine.

A Russian airstrike hit Kharkiv in northeastern Ukraine around 3 a.m., hitting a house and killing four people, regional governor Oleh Syniehubov said. Nearly 20 houses were damaged in the attack, he said.

Hours earlier, Russia threw a glide bomb at the landmark Derzhprom building in central Kharkiv, wounding seven people, Mayor Ihor Terekhov said. Derzhprom, also known as the Palace of Industry, is being considered for inclusion in the UNESCO World Heritage List.

Terekhov said Russia has concentrated attacks on Kharkiv in recent days. He urged people not to ignore air raid warnings.

Authorities in Kiev said debris from intercepted Russian drones fell on two city districts, injuring six people.

Ukraine has also used long-range drones to disrupt Russia’s war machine and embarrass the Kremlin by attacking targets on Russian soil.

A special forces academy in the Russian province of Chechnya was hit by drones, causing a fire that was quickly put out, according to Chechen leader Ramzan Kadyrov, who is a close ally of Russian President Vladimir Putin.

It was the first drone strike in the war against Chechnya, which is about 800 kilometers (500 miles) east of Ukraine.

Associated Press writers Aamer Madhani and Lolita C. Baldor in Washington and Jill Lawless in London contributed to this report.