Tokyo is planning to name 39 uninhabited islands, including several adjacent islets of the Diaoyu Islands, Japan's Chief Cabinet Secretary Osamu Fujimura said on Monday at a news conference.
The claim sparked concerns again on the lingering territorial dispute between China and Japan.
The Japanese government is working with the Geospatial Information Authority of Japan (GSI) to investigate seven unnamed adjacent islets of the Diaoyu Islands, Japan's Fuji Television said on Monday.
The Cabinet Secretary said the 39 islands are among the cardinal points selected by the Japanese government to help define its so-called exclusive economic zone (EEZ), according to Japan's Sankei Shimbun newspaper's website.
"The names (of the islands) will be finally decided within the year," he said. The government will reportedly determine the guidelines of naming the islands in March.
On Monday, Chinese Foreign Ministry spokesman Liu Weimin said that the Diaoyu Islands and adjacent islets have been an inherent territory of China since ancient times, over which China has "indisputable sovereignty".
"Our determination to protect China's sovereignty over the Diaoyu Islands is unremitting," Liu said.
After deciding the final version of the names, GSI and Japan's Coast Guard will put the names on the updated version of related maps, according to Sankei.
The naming of the islands is aimed at helping Tokyo to lay claim on its EEZ and "enhancing control" on the islands, Fuji TV reported.