China and South Korea have condemned Japanese Prime Minister Shinzo Abe for visiting a shrine that honours war dead including convicted war criminals.
Seoul said it was furious with the “deplorable” act, and Beijing labelled the visit “absolutely unacceptable” and summoned Japan’s ambassador.
Japan’s neighbours see the Yasukuni shrine as a symbol of the militarism of Japan during and before World War Two.
US officials said the visit would “exacerbate tensions” in the region.
China, Japan and South Korea are embroiled in a number of disputes over territory in the East China Sea.
The disputes have helped to fuel nationalist passions in all three countries.
Mr Abe’s Yasukuni visit, the first by a serving prime minister since Junichiro Koizumi went in 2006, was televised live.
“It is not my intention at all to hurt the feelings of the Chinese and Korean people,” said Mr Abe, who claimed his visit was an anti-war gesture.
Officials said Mr Abe visited the shrine in a private capacity and was not representing the government.
But shortly after, China summoned Japan’s Beijing envoy to lodge a “strong protest”.
Chinese Foreign Ministry spokesman Qin Gang said Beijing seriously condemned the visit.
“This poses a major political obstacle in the improvement of bilateral relations. Japan must take responsibility for all the consequences that this creates,” he said.
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