North Korea is sending thousands of construction workers to help rebuild a war-torn Russian border region, a Russian official said Tuesday, as the Kremlin boasted of new steps in the deepening partnership between the two countries.

Sergei K. Shoigu, a close aide to President Vladimir V. Putin, met with Kim Jong-un, the North Korean leader, in Pyongyang on Tuesday. It was his third visit to the North Korean capital since March.

Afterward, he told reporters that Mr. Kim had agreed to send 5,000 construction workers and 1,000 sappers — combat engineers — to Russia’s Kursk region. That is where North Korean troops fought alongside Russian forces this past winter and spring to push Ukrainian soldiers out of several hundred square miles of Russian territory. The sappers, he said, will work on demining the region.

North Korea’s official Korean Central News Agency did not mention sending laborers to Russia in a Wednesday report on the meeting between Mr. Kim and Mr. Shoigu. But it said Mr. Kim had decided to cooperate with Russia based on “a correct understanding of the current situation.” It also said that Mr. Kim and Mr. Putin had been exchanging letters for several weeks.

In a video of Mr. Shoigu’s arrival distributed by Russian state media, Mr. Kim can be seen embracing the Russian visitor and telling him that “our cooperation is deepening.”

As many as 15,000 North Korean workers are already employed in Russia, South Korean intelligence officials said in April. Their labor violates U.N. Security Council sanctions but is of mutual benefit for both Moscow and Pyongyang. The North Korean government earns much-needed foreign currency by claiming much of the workers’ salaries, while Russia gets an infusion of help at a time when its labor force has been depleted by the war in Ukraine.