The gap between Japan and its neighbors over war history is deepening, with Chinese and Koreans sharply critical of Tokyo but most Japanese believing they have apologized enough, a survey said Thursday.

The survey by the US-based Pew Research Center found overwhelming sentiment in South Korea and China that Japan has not shown enough contrition, with a mere one percent of South Koreans saying Tokyo has apologized sufficiently.

Perceptions have worsened in recent years, with the percentage of South Koreans who see Japan favorably slipping by 25 points since 2008 and the same figure sliding by 17 percentage points in China.

Only 22 percent of South Koreans and four percent of Chinese said they saw Japan in a positive light, according to the survey, which polled adults in eight nations by telephone or in person in March or early April.

Bruce Stokes, the report's author, said there was not data to determine whether hardening attitudes were linked to the return to power in December of Japanese Prime Minister Shinzo Abe, who is known for his conservative views of history.

But Stokes said that the attitudes were clearly influenced by a series of incidents including Japan's approval of controversial textbooks and statements questioning the facts behind "comfort women."

Some 200,000 women from conquered territories were forced into wartime brothels for Japanese soldiers but right-leaning politicians -- including Abe before he took office -- have cast doubt on the extent of Japan's role.

Japan apologized to former comfort women in 1993 and issued a broader apology for wartime suffering two years later, leading some Japanese officials to accuse neighboring countries of deliberately keeping tensions alive.

A left-leaning government set up a fund to compensate former comfort women, but it could not operate in China and most South Koreans refused the money because the funds came from private donors.

Historical disputes cloud Japan's relations with its neighbors. The United States has been concerned over the lack of coordination between Japan and South Korea, US allies that share common interests on North Korea and other issues.

The poll found that 48 percent of Japanese believed that they have already apologized enough for the war and that another 15 percent believed that no apology was necessary in the first place.

Such views were particularly strong among Japanese between 18 and 29 years old, among whom 73 percent said that the country has already asked for enough forgiveness or did not need to apologize.

The poll found little enthusiasm among Japanese for revising the US-imposed post-World War II constitution's key Article Nine, under which Japan forever renounced the right to wage war.

But while 56 percent said they opposed revising Article Nine, the figure is down from 67 percent in the same poll in 2006.

Abe has long been passionate about revising the constitution, although he has appeared to put the issue on the backburner to focus on the economy and has enjoyed unusually strong public support six months into his tenure.

The poll showed a much different picture in Southeast Asia, with Japan widely liked in Indonesia, Malaysia and the Philippines -- countries that also experienced occupation by imperial Japan.

In a sign of how little Northeast Asia's historical disputes resonate in Southeast Asia, nearly four in 10 Malaysians did not offer an opinion on whether Japan has sufficiently apologized.