Russian President Vladimir Putin has reaffirmed his "friendship" with North Korean leader Kim Jong Un, ahead of his talks with Donald Trump on Friday.
It also comes as the BBC reported the "slave-like" condition facing thousands of North Korean workers sent to Russia to take part in construction projects.
Putin and Kim spoke on Tuesday, with the Russian leader praising Pyongyangs military support for his countrys war against Ukraine.
This week, Russia has been making fresh military advances in Ukraine, leading to a sudden thrust near the eastern town of Dobropillia and advancing 10km (six miles) in a short period of time.
Kim and Putin "reaffirmed their commitment to the further development of friendship relations, good-neighbourliness and cooperation," the Kremlin said in a statement.
Putin gave the North Korean leader an update on the Alaska summits preparation, sharing with him "information in the context of the upcoming talks with US President Donald Trump," the Kremlin said.
The official North Korean statement did not mention this.
Repeating his earlier statement, Putin "praised the assistance provided by [North Koreas] support during the liberation of the territory of the Kursk region", according to his office.
The Ukrainian army briefly invaded Russias Kursk region last year in an unexpected offensive that showed Western allies its capability to fight back against Russia, which currently occupies about 20% of Ukraines territories.
Putin and Kim spoke just days before the Russian leader is expected to travel to Alaska to meet Trump, his first face-to-face meeting with a US president since Russias full-scale invasion of Ukraine in February 2022.
The war, while causing Russia near-complete economic and diplomatic isolation from the West, has seen unprecedented collaboration between Moscow and Pyongyang. At least 10,000 North Korean soldiers have been sent to fight side by side with their Russian counterparts, according to Ukraine and South Korea.
North Korea also provided Russia with missiles, artillery shells and labourers.
With many of Russias men either killed or tied up fighting - or having fled the country - South Korean intelligence officials have told the BBC that Moscow is increasingly relying on North Korean workers.