By Mahmut Atanur
BEIJING (AA) – China's defense ministry has reportedly refuted Japan's protest over Chinese warships sailing close to the Diaoyu Islands in the East China Sea.
Japan’s defense ministry had said Thursday that it would take action to protect its sovereignty, after claiming that a Chinese frigate had sailed close to its waters.
On Friday, China's People's Daily quoted the ministry underlining in a statement released on its official Weibo account that the Diaoyu Islands -- which Japan refers to as the Senkaku islands -- and its affiliated islands are China's inherent territory.
"The sailing of Chinese warships through waters under its own jurisdiction is reasonable and legitimate," the ministry said.
According to Kyodo news agency, the frigate entered the zone northeast of Kuba Island, part of the Senkakus, around 00.50 (1650GMT Wednesday).
The ship reportedly left the waters and headed north without intrusion to Japanese territorial waters, the ministry added.
Kyodo quoted Chief Cabinet Secretary Yoshihide Suga as saying Thursday morning that the issue raises tensions between the two countries and called it deeply concerning.
"The Senkaku Islands are inherently part of Japanese territory on the basis of history and international law," Suga told a press conference.
"The government will take a resolute stance in fully protecting our territory on land and at sea."
It reported that China's Ambassador to Japan, Chen Yonghua, had been summoned by Japan's Vice Foreign Ministry Akitaka Saiki after Saiki expressed grave concern and lodged a protest over the issue.
The Senkakus are a group of uninhabited islets currently in the East China Sea.
China is pushing claims in areas of the neighboring South China Sea where other Southeast Asian governments have overlapping claims.
The U.S. has expressed fears that Beijing's buildup of airstrips on artificial islands it has built on once-submerged reefs could impede freedom of navigation in the area.