China's defense ministry has confirmed that Chinese and Japanese fighter jets had a confrontation over disputed waters in the East China Sea last month, and says the Chinese jets were only carrying out a routine patrol of the space.

The ministry said the Japanese fighters approached the Chinese jets at high speed to provoke them, which forced the Chinese pilots to take "tactical measures." The statement issued Monday did not say what the measures were.

The encounter June 17 took place near a set of barren islets claimed by both countries, called Diaoyu islands by Beijing and Senkaku islands by Tokyo.

China in 2013 set up an air defense identification zone that covers the islands and overlaps with Japan's claim of air space for defense.