South Korea sent a diplomatic document to Japan on Thursday, dismissing Tokyo's latest proposal to take the sovereignty issue of South Korea's easternmost islets of Dokdo to the International Court of Justice (ICJ).

Last week, Tokyo handed over to Seoul a "note verbale," a diplomatic document that is unsigned but more formal than a verbal request, suggesting that both sides jointly refer the Dokdo issue to the ICJ for settlement.

In its reply delivered to Tokyo via a diplomatic channel here, South Korea made it clear once again that "no territorial disputes exist about Dokdo," which is South Korea's territory historically, geographically and under international laws, according to the Seoul's foreign ministry.

The Japanese proposal is not feasible as it must secure South Korea's consent to have the issue dealt with by the ICJ, according to the ministry. Two similar proposals by Japan in 1954 and 1962 were also instantly rejected.

Tension has heightened in recent weeks after Tokyo strongly protested President Lee Myung-bak's unprecedented trip to Dokdo on Aug. 10. Bilateral relations deteriorated further after Lee later called on Japanese Emperor Akihito to apologize if he wishes to visit South Korea.

Japan has frequently laid claims to South Korea's rocky outcroppings of Dokdo in the East Sea, stoking enmity in South Korea against its former colonial ruler.

South Koreans see those claims as amounting to denying Korea's rights because the country regained independence from the 1910-45 Japanese colonial rule and reclaimed sovereignty over its territory, which includes Dokdo and many other islands around the Korean Peninsula. (Yonhap News)