Kim Jong-un wrote to Vladimir Putin promising to boost ties as North Korea and Russia marked the 75th anniversary of bilateral relations. The North Korean leader congratulated the Russian president on his victory over what he called “hegemony and pressure from imperialists”. He also wished his Russian ally luck in resisting pressure from their common nemesis West over Ukraine. "I hope that the Russian people, who have set out to build a strong nation, will always achieve only victory and glory in their struggle to protect the country’s sovereignty, dignity, security and peace by crushing the imperialists’ persistent hegemonic policy and anti-Russia scheme to isolate and stifle it," the North Korean leader said, as reported by Pyongyang’s state media KCNA. He added that he was extremely satisfied with their "candid, comprehensive" talks during recent visit to Russia’s far east last month. Mr Kim said he is pledging to further develop relations to a "new height". He expressed the “firm belief that the bilateral friendship and solidarity and cooperation, consolidated generation after generation and century after century, will steadily develop onto a new level in the future, too”. Mr Putin also sent a letter to Mr Kim and said their latest meeting was more evidence of developing ties. "I am convinced that to implement the agreements will contribute to further expanding the constructive bilateral cooperation for improving the well-being of the peoples of the two countries and ensuring security and stability in the Korean peninsula and Northeast Asia as a whole," the Russian president said. The exchange of letters between the two allies comes nearly a month after Mr Kim made an elaborate six-day visit to Russia, breaking his self-imposed lockdown on foreign visits. Both leaders, united in their fight against the West, discussed military cooperation, a speculated weapons deal and North Korea’s satellite programme. Foreign officials suspected that the North Korean leader was seeking sophisticated Russian weapons technologies in return for the munitions to boost his nuclear programme as recent satellite photos showed a sharp increase in rail traffic along the North Korea-Russia border. A minimum of 73 rail cars with packages covered in tarpaulin left for Russia in the first week of October, sparking wide speculation that North Korea was now aiding Russia in military equipment. Officials in the US and South Korea warned that North Korea and Russia would face consequences if they went ahead with the reported weapons transfer deal in violation with UN Security Council resolutions that ban all weapons trade involving North Korea. Read More US aircraft carrier arrives in South Korea as North's leader Kim exchanges messages with Putin Satellite images show spike in border activity as North Korea ‘supplies weapons to Russia’ for Ukraine war A surge in rail traffic on North Korea-Russia border suggests arms supply to Russia, think tank says North Korea vows strong response to Pentagon report that calls it a 'persistent' threat North Korean leader urges greater nuclear weapons production in response to a 'new Cold War'