South Korea has rejected Japan's latest protest over the issuance of stamps featuring an island in the Sea of Japan claimed by both countries, South Korea's Yonhap News Agency reported Sunday.

According to South Korean officials in Geneva, South Korea sent a statement to the 190 member countries of the Universal Postal Union saying Japan's recent protest to the U.N. agency responsible for postal services violates its right to sovereignty.

Tokyo on Thursday released a statement to union members claiming Seoul is guilty of reproachable behavior in going ahead with production of the controversial stamps, according to the report.

Mostly a cluster of small reefs, Takeshima, or Tok-do in Korean, is uninhabited and roughly equidistant from the Korean Peninsula and Honshu.

South Korean postal authorities issued the stamps Jan. 16 despite pleas from Japan.

In its protest to the UPU, Japan said Takeshima is Japanese territory illegally occupied by South Korea, and the stamp issue not only will harm friendly bilateral relations but will have no impact on Japan's view of the islets.

In response, the South Korean statement said the island is South Korean territory based on historical documents, geographical circumstances and international territorial laws.