SEOUL, Oct 24, 2025 (BSS/AFP) - North Korea has begun building a memorial for soldiers killed fighting in Russia's war with Ukraine, state media said Friday, with leader Kim Jong Un hailing a "historic peak" in ties with Moscow.

The so-called Memorial Museum of Combat Feats will be built in the capital Pyongyang, where Kim and Russia's ambassador to North Korea attended a groundbreaking ceremony, according to the Korean Central News Agency (KCNA).

Kim, addressing the event, said the museum "is a sacred sanctuary dedicated to the immortality of true patriots".

North Korea, one of the world's most diplomatically isolated nations, has deepened ties with Russia since Moscow invaded Ukraine in February 2022.

It has sent thousands of soldiers and container loads of weapons to help the Kremlin push Ukrainian forces out of western Russia.

At least 600 North Korean soldiers have been killed and thousands more wounded, according to estimates from South Korea.

In remarks carried by KCNA, Kim praised his country's troops for helping Russia achieve a "decisive victory".

"Our heroes destroyed the fiendish neo-Nazi invaders with their staunch spirit not to tolerate any aggression but to annihilate the aggressors," Kim said.

North Korea and Russia's relationship was "now rising to its historic peak", he added.

"Pyongyang will always be with Moscow. Our friendship and unity will last forever," Kim said.

Kim said the memorial would feature sculptures dedicated to the North Korean soldiers who have fought in Russia, as well as photos and artwork portraying the combat.

Moscow's ambassador to North Korea, Aleksandr Matsegora, and other Russian embassy officials attended Thursday's ceremony, KCNA reported.

Several North Korean government and military officials were also present, along with families of soldiers who have died in Russia.

Images released by state media showed Kim embracing visibly emotional soldiers at the ceremony in the capital Pyongyang.

Russia and North Korea last year agreed to a strategic partnership agreement that obligates each side to provide "military and other assistance" should either of them be attacked.

In Moscow, an art exhibition has been held to celebrate ties with Pyongyang -- depicting North Korean soldiers and their Russian comrades resisting a hostile West.

North Korea only confirmed it had deployed troops to support Russia's war in Ukraine in April, and admitted that its soldiers had been killed in combat.

Washington has said there is evidence that Russia is stepping up support for North Korea, including providing help on advanced space and satellite technology, in return for its assistance in fighting Ukraine.