S.Korea lashes out at Japan over Korean Air boycott

In the latest flare-up in the long-standing territorial row, South Korea's foreign ministry said the directive by Japan was "disappointing and deeply regrettable" and urged Tokyo to withdraw the move.

South Korea has also summoned Japan's senior diplomat based in Seoul to protest the move.

Japanese Foreign Minister Takeaki Matsumoto this week told his ministry officials to refrain from flying Korean Air on their business trip for a month, after the airline made the test flight of its new Airbus A380 jet in June over the disputed islands -- called Tokto in Korean and Takeshima in Japanese.

The islands, located about the same distance from both countries' mainlands, have been a persistent irritant in their ties. South Korea controls the islands with a police presence.

The waters surrounding the islands are rich in marine life and popular with squid fishermen, while the seabed in the area may have deposits of a natural gas hydrate that could be worth billions of dollars.

Korean Air declined to comment on Japan's boycott, but said officials from the Japanese embassy in Seoul visited its offices this week to discuss the issue.

There is no data on how often Japanese diplomats use Korean Air, a Japanese foreign ministry official said.

South Korean media joined the fray, with one mainstream newspaper calling Tokyo's move "erratic and irrational."

Japan "must recognize that this latest move will only harm its international image as well as its national interests," the mainstream JoongAng Daily newspaper said in an editorial on Friday. (Additional reporting by Kiyoshi Takenaka in Tokyo; Editing by Yoko Nishikawa)