The North Korean leader, Kim Jong-un, has inspected Russian nuclear-capable strategic bombers, hypersonic missiles and warships, accompanied by Vladimir Putin’s defence minister. Sergei Shoigu greeted Kim at Russia’s Knevichi airfield, about 30 miles (50km) from the Pacific port city of Vladivostok, on Saturday. The North Korean leader then inspected a guard of honour. The US and South Korea fear the revival of Moscow’s friendship with Pyongyang could give Kim access to some of Russia’s sensitive missile technology while helping arm Russia in its war in Ukraine. Shoigu showed Kimstrategic bombers – the Tu-160, Tu-95 and Tu-22M3 – which are capable of carrying nuclear weapons and form the backbone of Russia’s nuclear air attack force, Russia’s defence ministry said. “It can fly from Moscow to Japan and then back again,” Shoigu told Kim of one aircraft. Kim was shown asking how the missiles were fired from the aircraft, at times nodding and smiling. Shoigu showed him the MiG-31I supersonic interceptor aircraft equipped with Kinzhal air-launched hypersonic missiles, which are capable of carrying nuclear or conventional warheads. The missile has a reported range of 1,500-2,000km (930-1,240 miles) while carrying a payload of up to 480kg (1,060lbs). It can travel at up to 10 times the speed of sound. Russia’s ambassador to North Korea, Alexander Matsegora, told reporters that Kim’s schedule was “very intense” and it was not clear how long he would remain in Russia, the Russian state news agency RIA reported. Kim inspected the Russian Pacific fleet’s frigate Marshal Shaposhnikov in Vladivostok and saw a demonstration of modern missile control systems, RIA said. South Korea and the US said on Friday that military cooperation between North Korea and Russia would violate UN sanctions against Pyongyang and that the allies would ensure there was a price to pay. Russia has gone out of its way to publicise Kim’s visit and drop repeated hints about the prospect of military cooperation with North Korea, which was established in 1948 with the backing of the Soviet Union. For Vladimir Putin, who says Moscow is locked in an existential battle with the west over Ukraine, courting Kim allows him to needle Washington and its Asian allies while potentially securing a deep supply of artillery for the Ukraine war. Washington has accused North Korea of providing arms to Russia, which has the world’s largest number of nuclear warheads, but it is unclear whether any deliveries have been made. On Friday, Kim inspected a Russian fighter-jet factory that is under western sanctions. He and the Russian president discussed military matters, the war in Ukraine and deepening cooperation when they met on Wednesday. Putin told reporters Russia was “not going to violate anything” but that it would keep developing relations with North Korea. The Kremlin’s spokesperson, Dmitry Peskov, told reporters there had not been a plan to sign any formal agreements during the visit. Russian diplomats said Washington had no right to lecture Moscow after the US had bolstered its allies across the world, including with a visit of a US nuclear-armed ballistic missile submarine to South Korea in July. While in Vladivostok, Kim watched the first act of the ballet Sleeping Beauty, staged by St Petersburg’s Mariinsky theatre, the RIA news agency reported.