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TOKYO — Japan released aerial photos of Chinese oil and gas exploration platforms Wednesday it said were close to disputed waters and proved that Beijing was planning to tap into an oil field that straddles both countries' territory.

"While the objects may be on the Chinese side of the dividing line, for China to unilaterally develop the natural resources there is extremely regrettable,” Japan's main government's main spokesman Yoshihide Suga told reporters during a press conference.

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In 2008, Japan and China agreed to jointly develop resources in the area, which is claimed by both countries.

Aerial photos of Chinese oil and gas exploration platforms in the East China Sea. Japanese Foreign Ministry Website / Japanese Defense Ministry

The new aerial photographs showed 16 Chinese platforms in the area, 12 of which have been built since 2013, Suga said.

"We decided to disclose what we can show, as there’s been increasing interest home and abroad over China’s unilateral efforts to change the status quo," Suga said, referring to a territorial dispute involving Vietnam and the Philippines over the Spratly Islands in South China Sea.

Related: China Has Some News About Disputed-Islands Project

On Tuesday, Japan's defense minister Gen Nakatani called on China to stop building the platforms, adding that Beijing's activities “were also of international concern."

China pushed back after Nakatani's statement.

"This kind of action completely lays bare the two-faced nature of Japan's foreign policy and has a detrimental impact on peace and stability in the Asia Pacific region," China's defense ministry said in a statement on Tuesday.