Prime Minister Shinzo Abe and senior Japanese officials have criticised China over two weekend incidents in which Chinese fighter jets came “dangerously” close to Japanese surveillance aircraft in the East China Sea.

The incidents occurred near an area in international waters where China and Russia were conducting joint exercises. China and Japan both claim the right to monitor and, if necessary, respond militarily to the presence of foreign aircraft in the area. Japan’s defence ministry said the fighters twice came within 30-50m of Japanese propeller-driven surveillance craft that were monitoring the exercises.

The episode is a reminder of the potential dangers stemming from a tense contest between Japan and China over influence in the area, which is home to the disputed Senkaku/Diaoyu islands and where both sides have frequently shadowed each other with ships and aircraft since 2012.