The Chinese public, once upbeat about US President Barack Obama, increasingly sees a hostile relationship with Washington but mostly still admires American democracy, a survey said Tuesday.

The poll by the Pew Research Center found that the Chinese held even dimmer views of other nations, with small numbers in the rising Asian power voicing favorable views toward the European Union, India, Pakistan and Iran.

Some 39 percent of Chinese said that they believed Beijing's relationship with the United States was one of cooperation, a sharp drop from 68 percent who said so two years ago, the poll found.

Twenty-six percent of Chinese said that US relations were hostile, a jump of 18 percentage points since 2010, with the rest of the public not offering an alternative assessment.

Only 38 percent of Chinese said they had confidence in Obama, a fall from a narrow majority in 2010 but still higher than George W. Bush's approval rating in China before he left the White House.

"We've seen attitudes towards the US and towards President Obama cool a little bit in different parts of the world since some of the initial enthusiasm that followed his election," said Richard Wike, associate director of the Pew Global Attitudes Project.

"But the change has been particularly sharp in China," he added.

Polls have shown that Obama still enjoys popularity ratings of more than 80 percent in Western Europe, Japan and South Korea.

Obama took office in 2009 calling for a broader relationship with Beijing, seeing opportunities for cooperation with the rising power on areas such as the global economic crisis to climate change.

But the Obama administration's views hardened in 2010 as Southeast Asian nations and Japan accused Beijing of aggressively staking claims to disputed territories.

Obama has since stepped up military cooperation in the region and defended freedom of navigation in the tense South China Sea. China has emerged as a campaign issue in US elections taking place on November 6, with Republican Mitt Romney accusing Obama of being too soft on trade and military issues.

Despite the changing perceptions of Obama, a vast majority of Chinese voiced admiration for US scientific achievements and 52 percent said they liked US ideas on democracy, with the numbers particularly high among urban Chinese with higher incomes and educations.

Only 29 percent said that they disliked US ideas on democracy. However, the public was closely divided on whether it would be good for US ideas and customs to spread to China.

Despite living in an officially communist state, 74 percent of Chinese said that most people were better off in a free market economy. However, a growing number of Chinese voiced concern about the gap between rich and poor and about corruption.

Forty-one percent of Chinese said that food safety was a "very big problem," a jump of nearly 30 percentage points since 2008 -- the year of a scandal in which the industrial chemical melamine was found to have been added to dairy products to give the appearance of higher protein.

The survey found that Chinese views were also largely negative about other countries. Only 23 percent of Chinese said they held a favorable view of India, with a sharp rise since 2010 in the percentage of Chinese who saw the fellow billion-plus nation as hostile.

India and China fought a war in 1962 and tensions have risen in recent years over their borders in two regions. India has for decades offered refuge to Tibetans fleeing Chinese rule, including the territory's spiritual leader the Dalai Lama.

China has provided military and economic support to India's historic rival Pakistan, whose leaders have often hailed the relationship with Beijing at times of tension with the United States.

But the Pew survey found that 31 percent of Chinese had a favorable view of Pakistan, only slightly better than their opinion of India.

"Pakistani views of China actually tend to be quite positive, but Chinese views of Pakistan are not the same," Wike said.

The survey, part of a 21-nation study, included 3,177 face-to-face interviews in China in March and April and had a margin of error of 4.3 percentage points.