The Diaoyu Islands are a group of uninhabited islands located roughly due east of mainland China, northeast of Taiwan, west of Okinawa Island, and north of the southwestern end of the Ryukyu Islands. They are currently controlled by Japan, which calls them Senkaku Islands. Both China and Taiwan claim sovereignty over the islands.
Japan draws up Diaoyu Islands contingency plan
Defence spokesman says forces are on alert over possible arrival of 2,000 Chinese fishing boats
Julian Ryall in Tokyo
Japanese authorities insist they are prepared to deal with any contingency involving the Diaoyu Islands, but they may struggle to cope with an armada of 2,000 Chinese fishing boats that is apparently headed for the disputed waters.
A spokesman for the Ministry of Defence in Tokyo confirmed discussions are ongoing between the government and the different arms of Japan's Self-Defence Forces and that a plan is in place if the coastguard is unable to deal with the situation alone.
"It will be the coastguard that will respond to any situations as the appropriate law enforcement agency, but if the situation goes beyond their capabilities then the Maritime Self-Defence Force or other SelfDefence Force units will be dispatched," a spokesman for the ministry said.
"We received a direction from the prime minister to keep collecting information and focus on providing warning patrols throughout the area," he added.
Xinhua and China Central Television on Sunday reported that nearly 2,000 fishing boats from Fujian and Zhejiang were heading towards the Diaoyus, after the end of a 3½ month ban on fishing in the East China Sea that was imposed by Beijing.
Monitoring of the area by Japan is being carried out by long-range P-3C Orion early-warning aircraft, although the spokesman declined to comment on whether surveillance flights had been stepped up.
The information that is being gathered is being shared with "all the relevant government agencies", he confirmed.
But the ministry also declined to comment on precisely how the coastguard and military might force the Chinese fishing boats to desist from their stated plans to enter the waters around the islands.
That situation will inevitably be complicated if Chinese fisheries protection vessels become embroiled in any confrontations or try to protect the fishing boats.
That would inevitably heighten the possibility of some sort of clash, possibly accidental, that could very quickly escalate into a far more violent confrontation.
Three Chinese surveillance ships briefly entered what Japan says were its territorial waters late yesterday, the coastguard said.
"I can tell you that Japan is very prepared for anything that might happen," the ministry spokesman said. "Having said that, our policy is to resolve this in a peaceful manner and we hope very much that the situation will not escalate."
After a relatively low-key response from the Japanese public, in contrast to the rising anger and violence in China, there have been several incidents.
Yesterday morning, two Japanese nationals briefly landed on Uotsuri Island but left aboard a small boat shortly afterwards.
On Monday evening, a man was arrested after hurling two smoke bombs into the grounds of the Chinese consulate.
The 21-year-old handed himself into police that evening.