TOKYO Japan on Friday was investigating whether online video clips that appeared to show a Chinese fishing boat colliding with Japanese patrol vessels were authentic, a development that could snarl efforts to mend ties.
Ties between Asia's biggest economies have chilled since September, when Japan detained the Chinese skipper of the boat which crashed into its ships near disputed isles in the East China Sea, the site of vast potential gas and oil reserves.
Beijing expressed concern to Japan about the video and the Chinese vice foreign minister warned that Tokyo should "avoid any obstruction" if it wants to improve strained relations.
The video is yet another headache for Japanese Prime Minister Naoto Kan's struggling government. It could, if genuine, harden Japanese public opinion against China by appearing to show the Chinese seaman, who was later freed, was at fault, and raises doubts about the government's handling of confidential data.
Kan has faced heavy criticism domestically for freeing the captain and tensions remain high, clouding the prospects for bilateral talks with Chinese President Hu Jintao at a November 13-14 Asia-Pacific leadership summit.
Russian President Dmitry Medvedev's visit this week to a disputed island north of Japan has also chilled Japan-Russia relations, and added to Kan's list of problems.
"We need to look into the authenticity of such clips," Chief Cabinet Secretary Yoshito Sengoku told a news conference.
Japanese TV news programmes also aired the video clips, which showed a blue boat bearing a Chinese name colliding with two patrol boats as sirens blared and Japanese crew shouted "halt."
"Generally speaking, if documents in a criminal suit have been released on YouTube and to the public, then that is a ... grave situation for investigation authorities," Sengoku said.
Japanese prosecutors released the captain but are still technically investigating whether to charge him.
Japanese Foreign Minister Seiji Maehara said China on Friday has expressed concern about the video through a diplomatic route, while Sengoku said he hoped Kan and Hu would meet bilaterally at the Asia-Pacific Economic Cooperation (APEC) summit in Yokohama, near Tokyo, next weekend.
The video clips appear to have been taken by the Japan Coast Guard, Maehara told reporters.
THREAT TO BUDGET
The government released the video for viewing by a small number of lawmakers but refused to make it public for fear of inflaming anti-Chinese sentiment.
Japan's opposition Liberal Democrats threatened to delay a 4.4 trillion yen (33.64 billion pounds) extra budget for the fiscal year to March 31 over the government's handling of the matter.
"This issue is related to national interests and sovereignty, so if the video is not released (to the public), I am not sure what will happen to the extra budget deliberation," Nobuteru Ishihara of the Liberal Democratic Party told reporters.
Tokyo, Washington and Southeast Asian nations have grown increasingly wary of a bullish China's intentions as it spends heavily to modernise its military, sends its navy further afield and asserts sovereignty over the contested South China Sea.
Beijing, which also claims the uninhabited isles in the East China Sea, known as Senkaku in Japan and Diaoyu in China, stressed that the video would not alter its stance in the feud.
"I think the rights and wrongs of the incident itself are very clear. The facts are clear cut," Vice Foreign Minister Cui Tiankai told reporters in Beijing.
"If the Japanese side is really serious and sincere about overcoming the current difficulties in the Sino-Japanese relationship and promoting strategic and mutually beneficial relations, then it should do everything in its power to avoid any obstruction."
Kan met Chinese Premier Wen Jiabao for a brief, informal chat an Asian summit in Hanoi last week in a bid to defuse the territorial dispute, after expectations of a formal meeting were dashed with China blaming Japan for "damaging the atmosphere."
(Additional reporting by Linda Sieg, Ben Blanchard and Chris Buckley; Editing by Edmund Klamann and Daniel Magnowski)