Japanese Prime Minister Shinzo Abe's visit to the Yasukuni Shrine on Thursday prompted Japan's own politicians, including one of Abe's political allies, to express their concerns about Japan's future path and its relations with Asian neighbours.
Critics included Natsuo Yamaguchi, leader of the New Komeito Party, which is part of the ruling coalition led by Abe's Liberal Democratic Party.
Yamaguchi said his party had urged Abe to avoid visiting the shrine, which honors Japanese leaders convicted as war criminals after World War II.
The visit "will make Japan's relations with China and South Korea tougher", Yamaguchi said.
He said the move was "regrettable".
Yamaguchi said Abe will have to face the impact his visit had on Japan's foreign relations alone.
He added that the prime minister clearly understood the ramifications of his visit.
Katsumasa Suzuki, secretary-general of Japan's People's Life Party, called Abe's move "unbelievable".
Social Democratic Party Secretary-General Mataichi Seiji said Abe initially vowed to follow an active pacifist road, but has instead engaged in active militarism.
Takehiko Yamamoto, a professor of international relations at Tokyo's Waseda University, told AFP the visit was "an act of folly" that will worsen a bad situation.
"It is perfectly possible the visit will fuel worries in Washington over a possible rise of militarism and a shift to the right in Japan," he said.
On Thursday, several Japanese political experts told Reuters that Abe likely calculated that his relatively high public approval could weather the criticism over his Yasukuni Shrine visit.
They said Abe's move will also shore up support in his conservative base.