TOKYO - Japan and China should try to resolve their differences calmly, China's ambassador to Japan said Saturday, a day after Tokyo filed a protest with Beijing over the intrusion of a Chinese nuclear submarine.
The incident has strained relations between two of Asia's biggest economic and military powers.
Japanese officials protested to the Chinese Embassy on Friday after Tokyo determined that the submarine, which had entered territorial waters days earlier, belonged to China.
China has yet to respond but on Saturday, Chinese Ambassador Wang Yi urged the countries to work toward improving relations.
"China and Japan have some problems, but we want both countries to respect each other and calmly find a solution," Wang said, avoiding specific reference to the incursion.
The nationally televised remarks came during a speech in Koya, a town in the Wakayama prefecture about 280 miles southwest of Tokyo.
Wang also said the Chinese are pained by Japanese homage to a Tokyo war shrine that Beijing says glorifies Japan's World War II atrocities in Asia. Japanese Prime Minister Junichiro Koizumi has paid annual visits to the shrine honoring the country's war dead.
Japanese Foreign Ministry spokesman Akira Chiba said he hadn't heard Wang's remarks.
"I know of no comments from China directed to the Japanese government," Chiba told The Associated Press.
Relations between Japan and China have cooled in recent months as the two sides have wrangled over underwater natural gas fields and several islands - known as Senkaku in Japan and Diaoyu in China - surrounded by rich fishing waters.
Tokyo is uneasy with China's growing military and economic might. Many Japanese worry about Beijing's military posture, which they see as increasingly hostile, amid China's booming demand for energy and marine resources and a historic rivalry with Taiwan.
Japan's navy went on alert Wednesday when the submarine was first detected in Japanese waters between the southern island of Okinawa and Taiwan. The submarine left after just two hours and headed north, and was shadowed by Japanese reconnaissance aircraft and naval destroyers.
Koizumi said Friday he did not expect long-term damage to ties with China but much depended on Beijing's response.
Japan's media have speculated that the incursion was the Chinese military's attempt to expose the Japanese navy's vulnerabilities and test its response.
On Saturday, newspaper editorials criticized Tokyo for being too soft on Beijing and urged the government to take military action against such intrusions at sea.
"It is not enough for Japan just to demand that Chinese vessel never invade Japanese waters again. Japan must make its own preparations to prevent China from repeating its violation of Japanese territory," the national Yomiuri newspaper said in an editorial Saturday that called Tokyo's response a "grave error."
"The way the Japanese government responded to China's violation of its territory was untenable," the paper said.
