Three Chinese ships have entered disputed waters off Tokyo-controlled islands in the East China Sea, according to the Japanese coastguard – the first such incursion this year.

The Chinese coastguard vessels sailed into the 12-nautical-mile territorial waters off one of the Senkaku islands about 1030 AEDT on Sunday.

China also claims the area, calling the islands the Diaoyus, Japan’s coastguard said.

The ships left less than two hours later.

Chinese state-owned ships and aircraft have approached the Senkakus on and off to demonstrate Beijing’s territorial claims, especially after Japan nationalised some of the islands in September 2012.

Sunday’s intrusion was the first since December 29 when three Chinese coastguard ships entered the zone and stayed for about three hours.