Three Japanese lawmakers pushing their country's claim to disputed islands were denied entry to South Korea on Monday but refused for hours to fly home from a Seoul airport, the justice ministry said.
The legislators finally left at 8.10 p.m., Yonhap news agency and KBS television said, nine hours after their arrival at Gimpo.
Yonhap said they departed after final warnings from immigration officials, who could not be reached for comment, that they would otherwise be held in detention like other illegal entrants.
"I will return to South Korea later," it quoted Yoshitaka Shindo as saying. "I will speak in detail about my position in a press conference in Japan."
Immigration officials had turned back the members of Japan's conservative opposition Liberal Democratic Party when they arrived in the morning.
For hours they rejected repeated requests to leave voluntarily, the justice ministry said.
In Tokyo top government spokesman Yukio Edano voiced regret and said Japan asked South Korea to "reconsider and allow them to enter."
"We have informed them that it is deeply regrettable that South Korea took such action against the lawmakers from our country," he said.
The three had planned to visit Ulleung island, the closest South Korean territory to the uninhabited Dokdo islands in the Sea of Japan (East Sea), which are known in Japan as Takeshima.
Hundreds of activists protested at Gimpo, waving banners asserting South Korea's ownership of the islands and burning photos of the lawmakers.
Some banners read "Stop Japan!" or "You die!" Other protesters carried a coffin plastered with photos of the lawmakers.
Shindo, the grandson of a general in the imperial Japanese army, has said in a video message on his website that "South Korea has illegally and militarily occupied part of what is undoubtedly our territory."
"We don't intend to fight there. We want to express our feeling of anger to the South Korean people," he said.
The two others were Tomomi Inada, a former lawyer who denies the 1937 Nanjing massacre by Japanese troops in China, and Masahisa Sato, a former member of the military.
At the airport, Shindo reiterated his country's claim to Dokdo.
"If our entry is denied, we will visit once again," he added, saying that the entry ban might evolve into a diplomatic row between the nations.
The latest spat began when flag carrier Korean Air mounted a test flight of its new A380 aircraft over Dokdo in June. Tokyo in response ordered public servants not to use Korean Air for a month.
South Korean President Lee Myung-Bak last week ordered officials to advise Tokyo that Seoul "cannot guarantee the lawmakers' safety" and to urge them to cancel the visit.
Older South Koreans still have bitter memories of Japan's harsh colonial rule over Korea from 1910-45. Seoul says it regained control over all of its territory, including Dokdo, at the end of the colonial period.
It posts a small coastguard force on Dokdo and has sought to strengthen its control over the islets after Tokyo in March authorised new school textbooks reasserting its claims.
North Korea, in rare agreement with Seoul, has denounced the lawmakers' planned trip.
"The Japanese reactionaries' recent moves are serious issues not to be tolerated by the Korean nation," the official news agency commented Saturday, saying the lawmakers intend to seize both Ulleung and Dokdo.© 2011 AFP