China has warned Japan it will not tolerate violations of its sovereignty, in high-level talks aimed at easing tensions over an islands dispute.
The comments, from Vice Foreign Minister Zhang Zhijun to his Japanese counterpart, were quoted on the Chinese ministry website.
The meeting came as dozens of Taiwanese boats sailed to the islands to protest.
The islands, called Senkaku in Japan and Diaoyu in China, are controlled by Japan but claimed by China and Taiwan.
Tension in the region has been high since Japan’s purchase of the islands from their private Japanese owner.
Taiwanese vessels, including coastguard ships, have now left the area.
Chinese surveillance and fishing boats have also been sailing in and out of waters around the islands in recent days, following the Japanese government’s announcement that it had bought the islands.
The row over ownership of the islands has been rumbling for years and has flared sporadically. This time, it has led to anti-Japanese protests in several Chinese cities.
Japan’s Vice-Foreign Minister Chikao Kawai arrived in Beijing on Monday for two days of talks.
“Because of the current difficult situation, I plan to explain what Japan is now considering to Zhang Zhijun and listen to what China is considering, for the importance of the relationship between both countries,” he said ahead of the talks.
The statement posted on the Chinese Foreign Ministry did not quote any comments from Mr Kawai. But it quoted Mr Zhang as telling him that Japan needed to mend its ways.
“China will never tolerate any unilateral actions by Japan that harm Chinese territorial sovereignty,” it said.
“Japan must banish illusions, undertake searching reflection and use concrete actions to amend its errors, returning to the consensus and understandings reached between our two countries’ leaders.”
The Japanese government moved to buy the islands in response to a potentially much more provocative plan by right-wing Tokyo Governor Shintaro Ishihara to buy and develop them using public donations.
The row comes at a time when both China and Japan are facing political changes domestically, making it difficult for either side to be seen as backing down.
Japanese Prime Minister Yoshihiko Noda’s government – already hit by poor figures in opinion polls – is likely to face an election in coming months. China is due to hold a party congress in weeks that will see major changes in the top echelons of leadership.
A ceremony to mark 40 years of ties with Japan – due on Thursday – has been put off. Last week, several major Japanese companies briefly suspended operations in China after attacks on shops and car dealerships.
Both China and Taiwan say they have inherited historic sovereignty over the islands. A flotilla of fishing boats sailed from Taiwan on Monday to protest over the issue.
A spokesman from Taiwan’s Coast Guard Administration told the BBC 58 fishing vessels arrived in the disputed waters at around 05:00 local time on Tuesday (21:00 GMT Monday), accompanied by several Taiwanese coast guard vessels.
Japan’s coast guard said warnings were issued to the boats and television footage showed water being sprayed towards the Taiwanese ships.
The flotilla turned back towards Taiwan after being in the area for a few hours, reports said.
The move to sail to the disputed area, activists and fishermen said, was to protect fishing rights and access to traditional fishing grounds.
“Fishing rights are more important than sovereignty, but fishing rights also means sovereignty (in this case),” activist Chen Chunsheng, who is organising the flotilla, told reporters on Monday.
”So for this day on which we negotiate fishing rights, we are willing to be the backing of the government.”