TENSIONS gripping east Asia have flared into a bitter war of words at a UN Security Council debate on war and peace.

The row started when Chinese UN ambassador Liu Jieyi said Japanese prime minister Shinzo Abe had "closed the door to dialogue with China" with his recent visit to a shrine where convicted second world war criminals are buried.

The envoys of North and South Korea also condemned the visit, then Japan rebuked its neighbours for raising their grievances in an open forum with envoys of more than 50 countries present.

The bitter exchanges played out for hours as each of the four countries took the floor twice to have a say.

East Asia's escalating disputes have alarmed the world, with the commander of US forces in the Pacific warning last week that tensions between China and Japan are likely to grow unless the two countries talk to each other.