By Linda Sieg and Kiyoshi Takenaka
TOKYO (Reuters) - Japan urged China on Monday to protect its citizens after anti-Japanese protests rocked Chinese cities on the weekend, and stressed that a feud over disputed islands in the East China Sea should not damage ties between Asia's two biggest economies.
Thousands of protesters took to the streets in Chinese cities on Sunday, with groups overturning Japanese cars and shouting slogans denouncing Japan's claims to the islands, known as the Senkaku in Japan and the Diaoyu in China.
The demonstrations came after 10 Japanese nationalists swam to the islands on Sunday in a tit-for-tat move following a similar landing by Chinese activists last week.
Both China's government, which faces a once-in-a-decade leadership change later this year, and Japan's Prime Minister Yoshihiko Noda, whose ratings have tanked since he took office last September and may be forced to call an election soon, are under domestic pressure to take a tough stance over the islands.
But close economic ties also mean the Asia rivals are wary of a rerun of the bitter drama that rocked relations in 2010 after Japan arrested a Chinese captain whose fishing trawler collided with a Japanese patrol boat near the uninhabited isles.
"Both countries do not want the Senkaku issue to affect overall bilateral ties. The Sino-Japanese relationship is one of the most important bilateral ties for Japan, and it is indispensable for the stability and prosperity of the Asia-Pacific region for China to play a constructive role," Japanese Chief Cabinet Secretary Osamu Fujimura told a news conference.
"We would like to continue to deepen mutually beneficial relations between Japan and China, keeping a broader perspective in mind," Fujimura said.
"Regarding the protests in China, we are asking, above all, to ensure the safety of Japanese nationals (in China)."
The anti-Japanese protests in part reflect bitter Chinese memories of Japan's occupation of large parts of China in the 1930s and 1940s.
Chinese mainstream media were critical of Japan, but some also suggested that violent protest was not the way to go.
"Japan has made a series of mistakes in the Diaoyu Island issue and has hurt the Chinese people's feelings," said the China Youth Daily.
"The young people's patriotism is laudable ... but for a selected number of those who are smashing their fellows' vehicles, damaging public property, that shows foolishness. This severely disrupts social order, injures the cities' image, and furthermore, affected China's image."
Japan, eager to keep the dispute with China from escalating, deported the Chinese activists within days of their landing. The fate of the Japanese protesters remains undecided.
The dispute parallels similar territorial rows between China and its southeast Asian neighbors that have sparked concerns about China's growing naval reach. It also comes as Japan's ties with South Korea worsen over a separate territorial row.
"On a rational basis, both sides have a lot to lose if this escalates. On the other hand, both have something to lose if they don't appear strong and assertive," said Jeffrey Kingston, director of Asian studies at Temple University's Tokyo campus.
"I think the ball is in China's court," he said. "My guess is that they want to put a cap on it. Whether they can do so is another matter.
Domestic pressures on both sides remain strong.
"You should put a few submarines and military fleets near the island, and when you see Japanese, immediately open fire ... said a Chinese microblogger. "Chinese officials are too timid. Even if this could start a war, Japan will not dare."
In Tokyo, Noda has come under fire for his handling of the incident from opposition parties keen to force an early election his Democratic Party looks likely to lose. Even some members of Noda's own party are talking tough.
"We need to consider various uses of constabulary forces, including the Self-Defense Forces (military)," Akihisa Nagashima, a special adviser to Noda on diplomatic and security matters was quoted as telling a TV programme on Sunday.
Japan's central government also faces a tough decision on whether to let the Tokyo Metropolitan government send officials to the islands to conduct a survey as part of a bid to buy the islands from their private Japanese owners.
Tokyo Governor Shintaro Ishihara, a harsh critic of China, proposed the purchase in April, prompting Noda to say the central government wanted to buy them instead. Both plans sparked outrage in China.
Chief Cabinet Secretary Fujimura said on Monday the government had returned the Tokyo Metropolitan Government's application to land on the islands, which the central government currently leases from its owners, because not enough information had been provided.
(Additional reporting by Sisi Tang in Hong Kong and Terril Jones in Beijing; Writing by Linda Sieg; Editing by Michael Perry)