Seoul  - South Korea on Monday summoned Japan's ambassador to protest reports that Tokyo plans to claim islets in the Sea of Japan as its territory in a revised curriculum handbook for its teachers.

Foreign Minister Yu Myung Hwan asked Ambassador Toshinori Shigeie to put a halt to any such plans, the Foreign Ministry said.

They concern the islets known as Dokdo in Korean and Takeshima in Japanese. Tokyo and Seoul have both made historical claims to the islets.

"Minister Yu emphasized that if the reports are true, it is an unfair attempt to undermine South Korea's ownership of Dokdo and it also runs counter to our efforts to move towards the future," ministry spokesman Moon Tae Young said.

The dispute came after Tokyo and Seoul vowed last month to put aside historical issues and improve their relations, which have been strained over issues stemming from the past, such as Japan's occupation of the Korean Peninsula in the first half of the 20th century.

The new handbook was not only to act as a guideline for teachers, but it was also expected to influence the content of future school textbooks.

Japanese media reports said the new handbook would claim the islets as Japan's, but a government spokesman in Tokyo said a decision on the teachers handbook had not been made.

Japan's Jiji Press news agency reported Monday that the Education Ministry was examining whether a change concerning the islets should be made to the new handbook, which would come into use in the 2012-2013 school year.

The islets are under the administration of South Korea, which claims them as part of an exclusive economic zone.

The islets, which are believed to be the site of gas deposits, lie 700 kilometres west of Tokyo and 450 kilometres south-east of Seoul. (dpa)