After Beijing demanded an apology for the illegally detained Chinese trawler captain, Tokyo replied Monday by saying China should compensate for the damage caused when the trawler collided with two Japanese patrol vessels.

"We will ask China to pay for damage incurred to coast guard vessels," the AP quoted Japanese Chief Cabinet Secretary Yoshito Sengoku as saying.

He was referring to a September 8 incident when a Chinese fishing boat collided with two Japanese Coast Guard patrol vessels in waters near the Diaoyu Islands.

Japanese authorities then illegally detained the trawler's captain until Friday.

China's Ministry of Foreign Affairs has said that Japan has provoked the current situation and should take all the responsibilities for the incident.

Citing sources from the China Fishery Law Enforcement Command, the China Fishing News reported that the command will send patrol boats to the Diaoyu Islands' waters regularly and will improve efforts to safeguard Chinese fishermen working in that area.

However, Sengoku said that Japan had requested that China pull back two fishery patrol boats from areas near the Diaoyu Islands.

Sengoku's words came a day after Japanese Prime Minister Naoto Kan rejected China's demand for an apology and compensation.

Also Monday, Japanese Foreign Minister Seiji Maehara summoned the Chinese ambassador in Tokyo, Cheng Yonghua, to demand regular access to four Japanese nationals who are being investigated in China for having entered a military zone without authorization and illegally videotaped military targets in Hebei Province.

Feng Zhaokui, deputy director of China Society of Sino-Japanese Relations History, said that it is likely that the Japanese government made the spate of moves to appease domestic opposition against the decision to free the Chinese captain.

"There has been an outcry among Japan's public, media and opposition party after the release of the Chinese captain, despite the fact that Japan broke the Fishery Agreement signed with China in 1997," Feng said. "This is because Tokyo has long been inculcating its people that the Diaoyu Islands are its territory, which is not the truth."

Confrontation will hurt both countries, as China and Japan are economically dependent on each other to a great extent, Feng added.

There are concerns that the diplomatic row between China and Japan might spill over into areas of trade and economy.

The Japanese newspaper Yomiuri Shimbun reported Monday that Beijing has toughened customs-clearance procedures of shipments to and from Japan in the city of Shanghai and provinces of Fujian, Guangdong and Liaoning.

However, an official of the General Administration of Customs told the Global Times on condition of anonymity that there hasn't been a stiffened inspection of shipments to and from China.