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Japanese Prime Minister Junichiro Koizumi (search) prayed Monday at a Tokyo shrine honoring the country's war dead, defying critics who say the visits glorify militarism and triggering angry protests from China and South Korea.

The visit was Koizumi's fifth to the Yasukuni Shrine (search) since becoming prime minister in April 2001 and came despite South Korea, which suffered from Tokyo's conquest of East Asia in the first half of the 20th century, immediately filed protests with Japanese officials.

Chinese Foreign Minister Li Zhaoxing (search) summoned Japanese ambassador Koreshige Anami to Beijing, saying the shrine visit "severely damaged China-Japan relations," the ministry said on its Web site.

"The Chinese government and Chinese people express strong anger," it said.

Noting that this year is the 60th anniversary of the end of World War II and that Koizumi had apologized for Japan's wartime aggression, China said the leader had "swallowed his own words."

China and Japan also canceled a planned meeting between envoys to discuss disarming North Korea.

In Seoul, South Korean Foreign Minister Ban Ki-moon summoned Japanese Ambassador Shotaro Oshima to express his country's "deep regrets" over the visit.

"Our government has repeatedly requested that [Koizumi] not visit the shrine, which enshrines war criminals who inflicted indescribable suffering and pain in the past," Ban told Oshima.

Later, South Korea's presidential spokesman Kim Man-soo said a summit between President Roh Moo-hyun and Koizumi scheduled for later this year would be "difficult unless there is a significant change in the situation."

Japan's embassies in Beijing and Seoul issued warnings urging Japanese citizens to be cautious, officials said. Demonstrations were held outside both embassies, though they were far smaller than the anti-Japanese riots that erupted in several Chinese cities in April over nationalist Japanese history textbooks.

Koizumi defended his visit, saying he went to Yasukuni to express Japan's resolve not to go to war again. He also said foreign governments should not interfere with his visit.

"A foreign government should not take issue with the way the Japanese express condolences to the Japanese war dead," he told a group of reporters.

Japan's 2.5 million war dead are worshipped as deities at Yasukuni, a shrine belonging to Japan's native Shinto religion. They include executed war criminals from World War II such as then-Prime Minister Hideki Tojo. The shrine also runs a museum that attempts to justify Japan's wartime aggression.

Speculation over a Yasukuni visit had been high following Friday's passage of Koizumi's long-cherished postal reform bills, which strengthened his grip on power.

"Koizumi is riding on a mood in government that nobody can speak against him now," political analyst Minoru Morita said. "He even ignored the court ruling to deliver a message that he is a ruler who makes his own decisions."

"But Mr. Koizumi blew a chance to mend Japan's troubled relations with China and South Korea," Morita said. "I'm afraid Japan's ties with [them] would be dangerously low."

Koizumi suggests the visits are personal, not official, but as in past occasions, he went to Yasukuni in an official car, accompanied by his aides. However, Koizumi made Monday's visit in a business suit rather than traditional Japanese dress, and he only stood outside the shrine's entrance rather than entering the inner chamber as in the past.

Koizumi "did not visit the shrine as an official duty of the prime minister," Chief Cabinet Secretary Hiroyuki Hosoda said.

Koizumi's visit received mixed reaction from within his ruling coalition and criticism from the opposition.

"We find [the visit] regrettable," said Takenori Kanzaki, head of the ruling Liberal Democrats' coalition partner, New Komei Party.