Japan urged China to ‘stay calm’ after Japanese lawmakers visited a shrine commemorating the war dead, quickly infuriating Beijing, reflecting how already-rigid relations are marred by historical events.

Koichiro Gemba, Japan’s foreign minister, downplayed the visits made by former Japanese Prime Minister Shinzo Abe and other senior government officials and cabinet members to the Yasukuni shrine, saying that they paid their respects as “private citizens” rather than government officials, Financial Times reports.

The “shortsighted and cowardly” visits stirred anger in China amid mounting tensions over territories in the East China Sea it deems as crucial to its sovereignty. China accused Japan of imperialism stemming from its colonial past. China’s foreign ministry spokesman Hong Lei demanded Japan “strictly abide by its solemn statements and pledges regarding historical issues.”

The disputed islands were “inherent territory of Japan based on historical fact and in light of international law,” Mr. Gemba said, reiterating Japan’s claim.

“I think it is necessary to think about the Senkaku Islands by delinking them from the past,” Mr. Gemba told Financial Times, adding that Beijing should “calm down the situation in a peaceful manner”.

This comes after a flotilla of Chinese warships were spotted near disputed waters.