RUSSIAN President Vladimir Putin and North Korean leader Kim Jong Un signed an agreement today that pledges mutual aid if either country faces “aggression” amid stand-offs with Western nations.

While the details of the deal were not immediately clear, both leaders described it as a major upgrade of their relations, covering security, trade, investment, cultural and humanitarian ties.

North Korea is under heavy UN security council sanctions over its weapons programme, while Russia also faces sanctions by the West over its invasion of Ukraine.

Mr Putin received a red-carpet welcome to the country, which he visited for the first time in 24 years, being greeted by roses and ceremonial gunfire at a grand military parade.

Mr Kim said the two countries had a “fiery friendship,” and that the deal was their “strongest ever treaty,” putting the relationship at the level of an alliance.

He vowed full support for Russia’s war in Ukraine.

Mr Putin called it a “breakthrough document” reflecting shared desires to move relations to a higher level.

Allied Western nations had expressed concerns ahead of the summit over a possible arms arrangement in which Pyongyang provides Moscow with munitions for its war in Ukraine, in exchange for economic assistance and technology transfers that could enhance the threat posed by Mr Kim’s nuclear weapons and missile programme.

At their talks, Mr Putin thanked Mr Kim for North Korea’s support in Ukraine, part of what he said was a “fight against the imperialist hegemonistic policies of the US and its satellites against the Russian Federation.”

Mr Putin’s foreign affairs adviser Yuri Ushakov said the leaders exchanged gifts after the talks.

The Russian president presented Mr Kim with a Russian-made Aurus limousine and other gifts.

Mr Ushakov said the North Korean presents to Mr Putin included artwork depicting the Russian leader.

US Secretary of State Antony Blinken said the visit illustrates how Russia tries, “in desperation, to develop and to strengthen relations with countries that can provide it with what it needs to continue the war of aggression that it started against Ukraine.”

Chinese Foreign Ministry spokesperson Lin Jian said high-level exchanges between Moscow and Pyongyang are “bilateral arrangements between two sovereign states.”

Victor Cha of the Centre for Strategic and International Studies said the pact represents a “renewal of cold war-era security guarantees.”