SEOUL -- Three Japanese lawmakers arrived in South Korea on a high-profile trip to an island near a set of disputed islets claimed by both countries, snubbing Seoul's warning to ban their entry.

Yoshitaka Shindo, Domomi Inada and Masahisa Sato, all members of Japan's opposition Liberal Democratic Party, arrived at Seoul's Gimpo International Airport earlier in the day on their way to the South Korean island of Ulleung, located some 90 kilometers away from the disputed islets.

Immigration officials here denied their entry, but the three lawmakers have yet to leave. Angry protesters staged demonstrations, throwing curry sauce on the floor, setting pictures of the lawmakers on fire and chanting anti-Japan slogans.

The move is seen here as the latest in a series of attempt by Japan to lay territorial claims to the set of rocky outcroppings lying halfway between the two countries, known as Dokdo here and Takeshima in Japan.

South Korea, which controls the East Sea islands, had officially notified Japan it would not authorize the conservative lawmakers' visit, voicing concerns for safety of the lawmakers and bilateral ties with Japan.

The much-publicized visit Monday by the conservative lawmakers copped some harsh criticism in South Korea, whose conflict-ridden relations with Japan date back to Tokyo's brutal 1910-45 colonial occupation of the Korean peninsula.

"The Japanese lawmakers have revealed their ulterior motives of stirring up territorial disputes over Dokdo by visiting South Korea despite diplomatic efforts by the South Korean government," the ruling Grand National Party said.

"The rash behavior by the Japanese lawmakers smacks of imperialism, and history will judge it," it added, urging the government to "reassess" diplomatic relations with Tokyo.

Seoul's special affairs minister, Lee Jae-oh, is currently on a four-day trip to Ulleung Island and the adjacent islets in question in a show of commitment to the South Korea-controlled islands.

South Korea says the disputed islets belong to the country " historically, geographically and by international law," while Japan describes the tiny islets as part of its territory in its school textbooks and official documents.

Monday's visit was reportedly prompted by the recent high- profile test flight to the disputed islets by South Korea's flagship airline, which reignited the decades-old diplomatic row between Seoul and Tokyo.

In response to the test flight by Korean Air's first Airbus A380, Japan's foreign ministry then instructed its officials not to fly with Korean Air for a month, calling the test flight "a violation of Japan's airspace."

The measure triggered angry responses from South Koreans, many of whom view Japan's resurgent territorial ambition as a sign it is not entirely repentant of its past as a colonial ruler.

South Korea has a coast guard unit stationed on the disputed East Sea islets, a show of its effective control. Its Navy, meanwhile, plans to expand the size of its air base on Ulleung Island by threefold, a bid to better guard the territorial waters surrounding the disputed islets.