Japan has lodged a protest with China over an article in a Chinese Communist Party newspaper that challenges Japanese sovereignty over the Ryukyu Islands, which include Okinawa, top government spokesman Yoshihide Suga said Thursday.
Tokyo told Beijing through diplomatic channels Wednesday it "strongly protests" if the article printed in the People's Daily represents the Chinese government's stance, Chief Cabinet Secretary Suga said at a press conference.
Suga said the Chinese side responded that the article, authored by two members of the state-run Chinese Academy of Social Sciences, was written in their capacity as researchers.
Later Thursday in Beijing, Chinese Foreign Ministry spokeswoman Hua Chunying told a news briefing that China "does not accept Japan's representations or protests" over the newspaper article.
Hua said Chinese academics have long paid attention to the history of the Ryukyu Islands and Okinawa, adding that the matter has become prominent again due to Japan's "provocative" actions regarding a group of disputed islands in the East China Sea, which are known as Diaoyu in China and Senkaku in Japan.
"The scholar-bylined article reflects the attention paid to and the research of the Chinese people and academics over Diaoyu and related historical issues and research," she added.
Japan's protest came amid heightened bilateral tensions over the Japanese-controlled, uninhabited Senkaku Islands after the Japanese government bought three of them from their private Japanese owner last year, effectively placing them under state control.
Okinawa Prefecture, which has administrative jurisdiction over the Senkaku Islands, is "unquestionably Japan's territory historically and internationally," Suga told the press conference.
But Hua, the Chinese Foreign Ministry spokeswoman, said the disputed islands are part of China's inherent territory and have never been part of the Ryukyus or Okinawa Prefecture. She accused Japan of violating China's territorial sovereignty.
The People's Daily article argued in part that ownership of the Ryukyus should be discussed anew on the basis of key historical documents, including Allied declarations from World War II that required Japan to return Chinese territory after its defeat.
The Ryukyus were once an independent kingdom, based in Okinawa, that paid tribute to Chinese emperors before it was absorbed by Japan in the late 19th century. Okinawa is now Japan's southernmost prefecture and hosts more than 70 percent of U.S. bases in Japan.