SEOUL: A group of South Korean lawmakers on Tuesday visited an isolated set of islands at the heart of a territorial dispute with Japan, a move likely to further stoke tensions with Tokyo.

Seventeen members of the parliamentary National Defense Committee flew to the Dokdo islands (known as Takeshima in Japan) on military helicopters for a day-long visit, an aide to committee member Han Ki-Ho said.

The trip—labeled a government inspection session—was aimed at checking security measures around the islands guarded by the South’s coastguard, the aide said.

On Monday, Japan’s chief cabinet secretary Osamu Fujimura had called on the Seoul MPs to cancel their visit, warning it would jeopardize bilateral ties.

The islands, which lie between the two countries, are controlled by South Korea but claimed by both nations.

Their long-standing row over ownership boiled over in August when South Korean President Lee Myung-Bak made a surprise visit to the islets.

Tokyo said the trip—the first ever by a South Korean president—was deliberately provocative.

Lee said it was designed to press Japan to settle lingering colonial-era grievances, including the issue of Korean women forced into sexual slavery for Japanese troops during World War II.

In August 2011, three conservative Japanese lawmakers tried to visit Ulleung island, the closest South Korean territory to the island chain, to voice their anger at Seoul’s “occupation” of the islets.

South Korean immigrations officers refused to allow them into the country, citing security concerns.

Japan is embroiled in a separate row with China over a different set of disputed islands in the East China Sea, which are also claimed by Taiwan.