The Japanese government has vowed a long-term approach in its bid to claim sovereignty over South Korea's Dokdo islets in the East Sea. 

Hiroshi Ando, parliamentary vice-minister of the Cabinet Office, announced the central government's stance on Friday at an annual Takeshima Day event in Shimane Prefecture.

Claiming South Korea’s easternmost islets as Japanese historically and under international law, he argued that resolving the issue is an important task for Japan. He said the issue will not be solved overnight and should be addressed based on a "100-year grand scheme" supported by the Japanese public. 

Ando said the Japanese government will continue surveys and research to support its claim to the islets and strengthen promotional efforts.