Japan's Prime Minister Shinzo Abe sent a gift to the controversial Yasukuni war shrine Monday, sparking a Chinese charge that he was offering "a slap in the face" to US President Barack Obama days ahead of his visit.

The unapologetically nationalist Abe donated a sacred "masakaki" tree to coincide with the start of a three-day festival, a shrine official said.

The sending of a gift has been seen as a sign that Abe does not intend to go to the shrine -- as he did on December 26, sparking fury in Asia and earning him a diplomatic slap on the wrist from the United States, which said it was "disappointed".

Yasukuni Shrine honours Japan's war dead, including some senior military and political figures convicted of serious crimes in the wake of the country's World War II defeat.

That, and the accompanying museum -- which paints Japan as a frustrated liberator of Asia and victim of World War II -- makes it controversial, especially in China and South Korea, where it is seen as a symbol of Japan's lack of penitence.

Abe and other nationalists say the shrine is merely a place to remember fallen soldiers. They compare it with Arlington National Cemetery in the United States.

Masaru Ikei, an expert on Japanese diplomacy and professor emeritus at Keio University, said that with Obama due to arrive on Wednesday for a state visit, Abe was always likely to stay away from the shrine.

"The prime minister does not want to worsen ties with China and South Korea before President Obama's visit, but he does want to maintain his creed that he should pray for the war dead," he told AFP.

Ikei said Washington's public and slightly unexpected rebuke after his last visit meant Abe "will not be able to visit the shrine again for a while".

Japan's chief government spokesman Yoshihide Suga on Monday sought to play down Abe's shrine gift, saying the government does not comment as the offering was "made in his capacity as a private person".

Asked about possible ramifications on the upcoming meeting between Abe and Obama, Suga said: "It won't affect the summit at all."

But Beijing offered a markedly different interpretation, lambasting the offering as "yet another provocative move detrimental to regional stability".

- 'Slap in the face' -

Coming just ahead of Obama's visit, "Abe's donation is nothing short of a slap in the face of the leader of Japan's closest ally," China's official news agency Xinhua said in a commentary.

Chinese foreign ministry spokesman Qin Gang, speaking at a regular briefing on Monday, said Japan needed to "face up to and deeply reflect on its history of aggression and make a clean break with militarism".

The South Korean foreign ministry also issued an angry statement.

"Our government cannot but deplore Prime Minister Shinzo Abe's offering to the Yasukuni Shrine, which enshrines war criminals, in glorification of Japan's past invasion and colonisation, as well as war aggressions," it said.

Many conservative lawmakers are expected to go to the shrine to mark the spring festival on Tuesday.

Two of Abe's cabinet ministers have already visited, saying they did not want the visits to interrupt their official duties.

Ties with South Korea have shown slight signs of improvement recently, following a three-way summit between Abe, Obama and President Park Geun-Hye and the visit to Seoul last week of a senior Japanese diplomat.

But relations with China remain sour.

In a further sign of their parlous state, Japanese shipping giant Mitsui O.S.K. Lines said China had seized one of its ships in a row over what Beijing says are unpaid damages relating to events in the 1930s.

That came after Japan began building a military installation in the far southwest of its long island chain, near the disputed Senkaku Islands, which Beijing claims as the Diaoyus.

The facility will bolster its ability to surveil China and is likely to further irritate Beijing, which regularly warns that Japan is re-militarising, while ramping up its own military spending and capacity.