Japanese and Chinese vessels engaged in a fresh standoff around disputed islands on Tuesday, the two countries¡¯ coast guards have said.

Relations have been strained since Japan¡¯s recently appointed Prime Minister Sanae Takaichi suggested last month that her country could intervene militarily in a Chinese attack on Taiwan.

The Japan Coast Guard said two China Coast Guard patrol ships entered Japan¡¯s territorial waters around the Senkaku Islands in the East China Sea in the early hours of Tuesday, and left a few hours later.

The Japanese-administered Senkaku Islands, known as the Diaoyu in China, have been a regular flash point between the two nations over the decades.

After the Chinese patrol ships sailed toward a Japanese fishing boat, a Japan Coast Guard vessel issued a demand that they leave the waters, the Japan Coast Guard statement said.

¡°The activities of Chinese coast guard vessels navigating within Japan¡¯s territorial waters around the Senkaku Islands while asserting their own claims fundamentally violate international law,¡± it said.

The statement added that the two Chinese vessels, and others, were still in the area.

China Coast Guard spokesperson Liu Dejun said that a Japanese fishing vessel ¡°illegally entered China¡¯s territorial waters.¡±

¡°China Coast Guard vessels took necessary control measures and made warnings to drive it away,¡± Liu said on the China Coast Guard¡¯s official WeChat account.

¡°The China Coast Guard will continue to conduct rights protection and law enforcement activities in the waters around the Diaoyu Islands, resolutely safeguarding national territorial sovereignty and maritime rights,¡± he added.

The development followed a similar incident around the islands on Nov. 16, around a week after Takaichi¡¯s comments, Kyodo News reported.

China claims self-ruled Taiwan as part of its territory and has not ruled out using force to take the democratic island.

Beijing has urged its citizens to avoid travel to Japan and a number of cultural events have been hit ¡ª including the halt of a performance by a Japanese singer in Shanghai on Friday.

Aside from reportedly renewing a ban on Japanese seafood imports, China has however so far stopped short of imposing more serious economic measures such as curbing exports of rare earth metals.