China on Monday lodged a protest with Tokyo after Japanese media quoted Japan's foreign minister as saying that a disputed border region between China and India belonged to India, in the latest source of friction between the two Asian rivals.
Japan's foreign ministry played down the issue, saying it could not confirm Japanese Foreign Minister Fumio Kishida's reported remarks. It added that it hoped India and China could resolve their dispute peacefully.
Tensions between China and Japan have risen in recent years, fueled by a row over a chain of uninhabited islets in the East China Sea. Their relations have long been poisoned by what China sees as Japan's failure to atone for its occupation of parts of China before and during World War Two.
Japan's Sankei Shimbun, a conservative daily, quoted Japanese Foreign Minister Fumio Kishida as saying in New Delhi on Saturday that Arunachal Pradesh that lies on the contested border was "India's territory".
China disputes the entire territory of Arunachal Pradesh, calling it south Tibet, especially Tawang, a key site for Tibetan Buddhism. The historic town briefly fell into Chinese hands during their 1962 war before Beijing retreated.
Kishida's reported remarks drew an angry response from China, which called on Tokyo to "understand the sensitivity of the Sino-India boundary issue".
"(We) have lodged solemn representations with Japan and have asked Japan to make clarifications and immediately eliminate the negative effects that have resulted from this," Foreign Ministry spokesman Hong Lei said at a daily news briefing.
Hong said that Japan has told China "it will not intervene" in the border dispute.
A Japanese Foreign Ministry spokesman said "the statement was made considering the reality that Arunachal Pradesh state is basically in reality controlled by India and that China and India are continuing negotiations over the border dispute".
"Japan hopes that the dispute will be peacefully resolved by negotiations between the two countries," he said, adding he could not confirm Kishida's remarks which were made during a Q&A session.