South Korean President Lee Myung-bak paid a landmark visit Friday to a set of disputed islets claimed by both South Korea and Japan, an unprecedented trip that raised Tokyo's ire.

The president visited the lonely East Sea outcroppings known as Dokdo here and Takeshima in Japan after a stop on the nearby Ulleung Island, some 90 kilometers west of the disputed islets, according to his office.

A self-professed pragmatist, Lee had largely avoided clashing headlong with Japan on outstanding historical issues even when the public sentiment at home dictated otherwise.

The trip, which made Lee the first South Korean leader to set foot on the islets coveted for rich mineral resources in its surrounding waters, came only four months before voters elect his successor.

It also came just a few days before South Korea celebrates the 67th anniversary of its independence from the Japanese colonial rule.

Japanese officials were up in arms, with Foreign Minister Koichiro Gemba warning the trip"would definitely have a large impact"on bilateral relations.

The Japanese authorities renewed their territorial claim over the islets in the latest defense white paper last month, which prompted Seoul officials to summon Japanese envoys in a show of protest.

South Korea has maintained its control of the islets for decades since the end of the 1910-1945 Japanese occupation. It is also building a naval base on Ulleung Island, a bid to better guard the Dokdo islands.

Lying equidistant between South Korea and Japan, the sparsely inhabited islets have been a chronic source of diplomatic row.

With the two Asian neighbors long at odds over historical issues, many South Koreans see the recurring territorial disputes as a sign of an unrepentant Japan.

Just last month, South Korea's attempt to forge its first military pact with Japan was thwarted at the last minute by the outraged public weary of Japan's resurgent military ambitions.

The outcry threatened to further isolate the unpopular president, whose foreign policy track record earned him a "pro- Japanese"label.

Friday's landmark trip met with mixed reactions at home. "The visit is meaningful in that it demonstrates his will to protect the country's sovereignty,"Lee's conservative ruling Saenuri Party said in a statement earlier in the day.

The opposition sounded less enthusiastic, claiming the trip was a political gimmick for domestic audiences. "The visit should not be a one-time event,"the main opposition Democratic United Party said in a statement."It is about time we sought practical measures to strengthen our control over Dokdo."