It said "Russian space forces' Tu-95MS strategic missile carriers and the Chinese air force's Xian H-6 strategic bombers carried out an aerial patrol over the Chukchi and Bering Seas and the north Pacific Ocean".

The statement came after the joint US-Canadian North American Aerospace Defense Command (NORAD) said American and Canadian warplanes had intercepted two Russian and two Chinese bombers in international airspace near Alaska on Wednesday.

It said the bombers "remained in international airspace" and were "not seen as a threat".

Moscow also said the patrol observed international law and did not breach foreign airspace, adding that "at certain stages of the route, the aviation group was accompanied by fighter jets of foreign countries".

The patrol was part of "a plan of military cooperation for 2024 and not directed against third countries," Moscow said.

Russia's defence ministry posted images of planes taking off and landing as well as footage from the air.

The TU-95MS planes were developed in the Soviet era to carry long-range cruise missiles and are part of Russia's nuclear triad. The Xian H-6 planes are also nuclear-capable.

China and Russia have drawn closer in recent years and hold joint military exercises regularly.

Beijing has strengthened its diplomatic, economic and military ties with Moscow since the start of the Russian offensive in Ukraine in February 2022.

Russian President Vladimir Putin visited China in May on his first trip abroad after re-election and met Chinese counterpart Xi Jinping again this month at a regional summit in Kazakhstan.

Russia said Sunday that it scrambled fighter jets to prevent two US strategic bomber planes from crossing its border over the Barents Sea in the Arctic.

The US military routinely carries out flights over international waters, operations that it says are conducted in neutral airspace, but Moscow has responded more aggressively in recent months.