Prime Minister Junichiro Koizumi suggested Tuesday he plans to worship at a controversial war shrine to mark the August 15 anniversary of Japan's World War II surrender, despite opposition from Asian neighbors who say the memorial glorifies the country's brutal militarist past.

Koizumi refused to clarify his plans, saying only that he would make an "appropriate" decision on whether to visit the Yasukuni Shrine in Tokyo, as pledged during his successful campaign for the premiership in 2001.

"My pledge is still valid," Koizumi said.

South Korean Foreign Minister Ban Ki-moon, in Tokyo for talks with Japanese officials, demanded Koizumi refrain.

"It is important that impediments be removed if we are to improve bilateral relations," Foreign Ministry official Shigeo Yamada quoted Ban as saying to his Japanese counterpart Aso Taro.

"Japan and South Korea should not be wasting time" over the spat, Yamada quoted Ban as saying.

Koizumi has worshipped at the shrine five times since he came to power, but never on August 15 _ something that many would see as a slap at South Korea and China. Japan's military invaded and occupied both countries in the first half of the last century.

China has not held summit-level talks with Japan since 2001, while top leaders from Tokyo and Seoul have not met since 2002.

Though Koizumi says he merely pays respects to fallen soldiers and prays for peace at Yasukuni many, even in Japan, oppose his visits.

The shrine played a high-profile role in stirring up wartime nationalism _ Japanese soldiers commonly pledged to fight to the death with a promise to "meet at Yasukuni" _ and honors men who planned and executed Japan's imperialist conquests in the 1930s and 1940s. It also hosts a museum that seeks to legitimize Japanese imperialism.

Koizumi's remarks came after Aso suggested Tuesday that only divorcing Yasukuni from its Shinto roots would allow government officials to pay their respects without controversy.

Shinto is Japan's indigenous religion, headed by the emperor.

"Rather than talking only about who visits when ... we must first reconsider what Yasukuni stands for," Aso told a press conference Tuesday.

The Asahi Shimbun daily also carried an editorial by Aso calling for Yasukuni to be made a nonreligious entity, thus allowing officials to pay their respects to the war dead without violating the separation between religion and the state as stipulated in Japan's constitution.

A top foreign policy concern in the region, Yasukuni has also become a key issue in the race to replace Koizumi when he steps down in September.

Chief Cabinet Secretary Shinzo Abe, a shrine supporter and front-runner in the race, reportedly worshipped at the shrine in secret earlier this year. But he has refused to confirm those reports or say whether he would go again as prime minister.

He rushed to Koizumi's defense Tuesday, calling the premier's decision on visiting the shrine a matter of religious freedom.

"Prime Minister Koizumi will decide for himself whether he will visit the shrine (on the 15th), within the constitutional right to freedom of religion," Chief Cabinet Secretary Shinzo Abe told reporters.

North Korea, meanwhile, criticized Abe's reported visit to Yasukuni, saying it was "an irresponsible act that did not take foreign relations into consideration," according to an official Pyongyang Broadcasting Service transmission monitored by Tokyo's Radiopress news agency.