Defense Minister Taro Kono mulled an aerial inspection this month of isles administered by Tokyo in the East China Sea that are claimed by Beijing, but he dropped the idea to avoid provoking China, a senior ministry official said Wednesday.

No Japanese defense minister has ever conducted an aerial inspection of the Senkaku Islands, called Diaoyu by China.

Kono had considered conducting the aerial inspection of the uninhabited islands to gauge how Japan's Self-Defense Forces would respond to a landing by an armed group, the official said.

The inspection was considered when Kono visited the Ground Self-Defense Force's missile batteries on Miyako and Yonaguni islands in Okinawa Prefecture on Aug. 8 and 9, the official said.

Tensions over the islands have been growing, with Chinese vessels spotted near them for 111 consecutive days through this month, the longest streak since Japan bought the islets from a private owner and put them under state control in 2012.

"When necessary, the Japan Self-Defense Forces will firmly act in coordination with the Japan Coast Guard," Kono said at a news conference earlier in the month.

But he fell short of elaborating on the circumstances in which the SDF would act.

In a meeting with Chinese Ambassador to Japan Kong Xuanyou on Aug. 18, Kono expressed concern over China's increased activities near the islands and Japanese airspace, requesting that it show restraint, according to the Japanese Defense Ministry.