Key Points

Kim made the remarks in a letter sent to Putin that congratulated the Russian leader on his birthday, according to a report by the North's Korean Central News Agency (KCNA).

"I do not doubt that the relations of alliance between the two countries, which have greeted the great heyday, will be invariably carried forward in the future, too, thanks to the warm friendly relations and close comradely ties between us, and will make a great contribution to powerfully propelling the comprehensive development of bilateral relations and establishing a just and multi-polarized world order," Kim told Putin, according to the KCNA report.

Since October last year, North Korea had sent about 15,000 troops and weapons to aid Russia's war efforts, according to South Korea's spy agency.

In the letter, Kim also said he will fully support the "just struggle" of Russia in defending its national sovereignty, apparently referring to Moscow's invasion of Ukraine, Yonhap news agency reported.

Earlier on August 13, North Korean leader Kim Jong-un had expressed his "full support" for Russia during his phone talks with Russian President Vladimir Putin, as the two nations have been deepening military cooperation.

Kim and Putin had held phone talks the previous day, KCNA had reported, marking the first time that the North has disclosed details about its leader's phone conversation with a foreign leader.

Kim had "expressed firm conviction that the DPRK would always remain faithful to the spirit of the DPRK-Russia treaty and fully support all measures to be taken by the Russian leadership in the future," the KCNA said.

DPRK is the acronym of North Korea's full name, the Democratic People's Republic of Korea.

- IANS