Russian President Vladimir Putin on Wednesday thanked North Korean leader Kim Jong-un for helping Russia oust Ukrainian soldiers from the Kursk region, saying they fought "heroically".

In a meeting with Kim in Beijing, Putin also praised their countries' "trust and friendship" and said sending the troops was the North Korean leader's idea.

Pyongyang has become one of Moscow's main allies since the conflict with Ukraine began three-and-a-half years ago, sending thousands of troops and container loads of weapons to help the Kremlin push Ukrainian forces out of western Russia.

"On your initiative, as is well known, your special forces took part in the liberation of the Kursk region," Putin said in a meeting with Kim.

"This was in full accordance with our new agreement. I would like to note that your soldiers fought courageously and heroically.

"We will never forget the sacrifices made by your armed forces and the families of your servicemen," he added.

Putin also invited Kim to visit Russia, according to video published by the Kremlin.

"See you soon," Kim said through an interpreter, hugging Putin goodbye after the talks that lasted two-and-a-half hours.

The North Korean leader last visited Russia in 2023.

The pair were among a group of foreign leaders attending a massive parade in Beijing on Wednesday marking the 80th anniversary of Japan's surrender following the Chinese People's War of Resistance Against Japanese Aggression and the World Anti-Fascist War. (AFP/Reuters)