A visit to the controversial Yasukuni war shrine by the Japanese Prime Minister has provoked an angry reaction from China and South Korea.
The Foreign Ministry in Beijing expressed its outrage at the visit by Shinzo Abe, the first by a serving prime minister in more than seven years.
South Korea says it can't withhold its anger at a visit to the shrine, which honours Japan's war dead - including convicted war criminals.
The United States says Japan's action will exacerbate tensions with its neighbours, the BBC reports.
Mr Abe described his visit, which is certain to roil already-troubled ties in east Asia, as a pledge against war and said it was not aimed at hurting feelings in China or South Korea.
The shrine is seen as the repository of 2.5 million souls of Japan's war dead, most of them common soldiers, but also including several high-level officials executed for war crimes after World War II, who were enshrined in the 1970s.
South Korea and China see it as a symbol of Tokyo's unrepentance and say it represents a misguided view of its warmongering past, the ABC reports.
"I chose this day to report (to enshrined spirits) what we have done in the year since the administration launched and to pledge and determine that never again will people suffer in war," said Mr Abe, dressed in a formal black swallow-tailed coat and a silver tie.
"I am aware that, because of misunderstandings, some people criticise a visit to Yasukuni shrine as an act of worshipping war criminals, but I made my visit to pledge to create an era where people will never suffer from catastrophe in war.
"I have no intention at all to hurt the feelings of Chinese or South Korean people.
"Like many prime ministers who have visited Yasukuni after the war, I wish to continue friendly relations with China and South Korea, which are important and benefit national interests."
Act of folly
The visit came exactly 12 months after he took power, a period in which he has met neither China's president Xi Jinping or South Korea's president Park Geun-Hye.
Ties with Beijing were bad before Mr Abe took office, with the two countries crossing diplomatic swords over the ownership of a string of uninhabited islands in the East China Sea, controlled by Japan, but claimed by China.
The dispute has been ratcheted up further this year, with the involvement of military aircraft and ships, leaving some observers warning of the danger of armed conflict between the world's second- and third-largest economies.
Takehiko Yamamoto, a professor of international relations at Tokyo's Waseda University, said the visit was "an act of folly" that was certain to make a bad situation worse.
"It is perfectly possible his visit will fuel worries in Washington over a possible rise of militarism and a shift to the right in Japan," he said.