South Korea’s foreign ministry summoned a Japanese diplomat on April 16 to protest against a claim in Japan’s annual diplomatic policy Bluebook on a group of islands at the centre of a longstanding territorial dispute, a ministry spokesman said, Report informs referring to Reuters.

Ties between the two countries have improved in recent years, but the neighbours are at odds over the sovereignty of the islands – called Dokdo in South Korea and Takeshima in Japan – that lie about halfway between them.

South Korea’s foreign ministry earlier said it “strongly protests” against the Japanese claim on the islands that were historically and geographically its sovereign territory.

Japan said in the Bluebook that the islands are its territory based on historical facts and under international law.

Tokyo had told Seoul its position on the islands was unacceptable, Japan’s top government spokesperson, Yoshimasa Hayashi, said.