(ATTN: UPDATES in para 5, 7, last 10 paras with Japanese reaction, background; ADDS photo)
By Chang Jae-soon
SEOUL, Aug. 10 (Yonhap) -- President Lee Myung-bak is expected to visit South Korea's easternmost islets of Dokdo on Friday, an unprecedented landmark trip that if realized, would unmistakably assert Seoul's sovereignty over the territory and could send diplomatic tensions with Tokyo soaring.
Lee could visit the rocky outcroppings lying in the East Sea around halfway between the Korean Peninsula and Japan "if weather allows for" the trip after he visits the nearby Ulleung Island, a senior presidential official said on condition of anonymity.
The trip, if it occurs, would make Lee the first South Korean president ever to visit the islets. It also comes days before South Korea observes Liberation Day on Wednesday, to celebrate Korea's independence from Japan's 1910-45 colonial rule.
The environment and culture ministers plan to accompany Lee on the historic trip, officials said, adding that the president is expected to remark during the trip that Ulleung Island and Dokdo should be preserved well in an environment-friendly way.
Officials declined to provide further details, citing security reasons.
The trip is expected to strain relations between Seoul and Tokyo.
Japan has long laid claims to Dokdo in school textbooks, government reports and other ways, undercutting better ties between the neighboring nations. Last week, Japan renewed the claims in its annual defense "White Paper" report outlining the country's defense policy.
This week, Japan also lodged a protest about Seoul's diplomatic "White Paper" describing Dokdo as Korean territory, officials said. It was the first time Japan has raised protests over the diplomatic report.
South Koreans see those claims as amounting to denying Korea's rights because the country regained independence from colonial rule and reclaimed sovereignty over its territory, including Dokdo and many other islands around the Korean Peninsula.
South Korea has kept a small police detachment on Dokdo since 1954.
The territorial claims have been viewed by South Koreans as a sign Japan has not fully repented for its imperialist past, along with Tokyo's refusal to address long-running grievances of elderly Korean women forced into sexual slavery for Japanese troops during World War II.
Japanese Foreign Minister Koichiro Gemba urged South Korea to call off the Dokdo trip.
"If the visit is made, it would go against our country's position and so we strongly urge its cancellation," Gemba told reporters in Tokyo, according to Kyodo News agency. "We must respond to it firmly."
Gemba also said the visit "would definitely have a large impact" on relations with Seoul.
Japanese media also reported that South Korea notified Tokyo of the planned visit, but officials in Seoul rejected those reports.
"Why do we have to notify Japan when our president goes to our territory?" an official said.
Lee has considered visiting Dokdo every year, but has not done so because weather and other conditions were not right, another presidential aide said.
Analysts said a visit by Lee to Dokdo could affect exchange projects with Japan, such as now-stalled efforts to forge what would be their first-ever military pact and negotiations to work out a free trade agreement between two of Asia's largest economies.
"Relations between South Korea and Japan cannot but be strained," said Chin Chang-soo, a senior analyst on Korea-Japan affairs for the Sejong Institute think tank. "Tensions could last for a long time."
The planned signing of the military information sharing deal was put on hold at the last minute in late June as criticism rose sharply in South Korea following revelations the Cabinet covertly passed the delicate pact with the former colonial ruler.
South Korea and Japan are key trade partners and cooperate closely in efforts to get North Korea to give up its nuclear weapons program. But issues related to the colonial rule have been a drag on their relations.
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