SEOUL - South Korea expressed strong regret over Japan's recent move to advise its foreign ministry officials against flying with Korean Air over the carrier's special flight near a set of disputed islets lying halfway between South Korea and Japan, local reports said Thursday.

Japan's foreign ministry reportedly instructed its officials not to fly with South Korea's flagship airline for a month, in protest against the demonstration flight last month by the airline's first Airbus A380 near the islets.

In response, South Korea demanded Japan immediately withdraw its measure against Korean Air, saying the country "accept any protests from the Japanese side over our national airline's flight to our territory," Yonhap News Agency quoted an unspecified foreign ministry official here as saying.

The lonely set of outcroppings in the East Sea, known as Dokdo in South Korea and Takeshima in Japan, has been a chronic source of diplomatic row between the two Asian neighbors.

South Korea has maintained its control of the islets for decades since the end of Japan's 1910-45 colonial rule, while Japan has repeatedly attempted to claim them as its territory.