China and South Korea have criticised Japan over its claims to contested islands, amid rising tensions between the Asian powers over maritime territorial disputes.

“The Japanese authorities have recently made a series of irresponsible remarks regarding the Diaoyu islands,” Senior Colonel Geng Yansheng, a Chinese defence ministry spokesman said on Tuesday. “Safeguarding the nation’s sovereignty and maritime interests is the joint responsibility of all state organs including the military. We will work closely with the other organs and conscientiously fulfil our duty.”

Regional tensions have been rising during the past couple of years over disputed waters in the South China Sea and East China Sea. Beijing and Tokyo have clashed repeatedly in recent months over the Senkaku islands – which China calls the Diaoyu – in the East China Sea which Japan has administered since 1895.