Google's threat to quit China over censorship and hacking intensified Sino-US frictions on Wednesday as Washington said it had serious concerns and demanded an explanation from Beijing.
China has not made any significant comment since Google, the world's top search engine, said it will not abide by censorship and may shut its Chinese-language google.cn website because of attacks from China on human rights activists using its Gmail service and on dozens of companies, including Adobe Systems.
Chinese authorities were "seeking more information on Google's statement," the Xinhua news agency reported in English, citing an unnamed official from China's State Council Information Office, the government arm of the country's propaganda system.
Friction over the Internet now seems sure to stoke tensions between the United States and China, joining friction over climate change, trade, human rights and military ambition.
With China the largest lender to the United States, holding $800 billion (491.5 billion pounds) in Treasury bills, these Internet tensions will make steering this vast, fast-evolving relationship all the more tricky, especially with the U.S. Congress in an election year.
"China has been taking a harder line," said Shi Yinhong, an expert on relations with the United States at Renmin University in Beijing. "The next few months are going to see some turbulence in China-U.S. relations. We may see some tactical concessions from China, but the general trend isn't towards compromise."
China has said it does not sponsor hacking.
Pressing China for an explanation, U.S. Secretary of State Clinton said: "The ability to operate with confidence in cyberspace is critical in a modern society and economy.
"We have been briefed by Google on these allegations, which raise very serious concerns," Clinton said in Honolulu.
Chinese industry analysts said the issue had snowballed beyond Google and its problems.
"If this becomes heavily politicised, and there are signs that it is, and people in the Chinese government say, 'This is good. It serves you right, and we won't bow our heads to the United States, then there'll be no way out," said Xie Wen, a former executive in China for Yahoo and other big Internet companies, who is now a prominent industry commentator.
"The impact on China's image will gradually also affect the enthusiasm of investors," he added. "It's not the pure economic losses -- a billion or so -- it's the deteriorating environment."
TENSIONS OVER INTERNET
China's policy of filtering and restricting access to Web sites has been a frequent source of tension with the United States and tech companies, such as Google and Yahoo Inc.
Google's announcement suggested the recent intrusions were more than isolated hacker attacks.
"These attacks and the surveillance they have uncovered -- combined with the attempts over the past year to further limit free speech on the Web -- have led us to conclude that we should review the feasibility of our business operations in China," Google's chief legal officer David Drummond said in a statement posted on the company's blog.
Some 20 other companies also were attacked by unknown assailants based in China, said Google.
RBC Capital Markets analyst Stephen Ju said the move was a turnaround for Google. "Just about every earnings call recently has been that they are focussed on the long-term growth opportunities for China and that they are committed."
Shares of Google dipped 1.3 percent although an executive described China as "immaterial" to its finances. Shares in Baidu, Google's main rival in China, surged 7 percent.
A Google spokesperson said the company was investigating the attack and would not say whether the company believed Chinese authorities were involved.
U.S. President Barack Obama, during a visit to China in November, told an online town hall that he was "a big supporter of non-censorship."
CHINA SILENT, NO BACKDOWN SEEN
After the Google announcement, searches on its google.cn search engine turned up images and sites previously blocked, including pictures from the 1989 crackdown on pro-democracy protests in Beijing. Other searches remained restricted, carrying messages warning users that some content was blocked.
China's ruling Communist Party, wary of the Internet becoming an uncontrolled forum for the country's 360 million Internet users, is unlikely to allow Google to avoid repercussions.
"Hostile Western forces have never abandoned their strategic schemes to Westernise and divide us, and they are stepping up ideological and cultural infiltration," the Party's chief propaganda official, Li Changchun, wrote last month.
If google.cn, launched in 2006, shuts down, Beijing could seek to restrict access to Google's main search engine, which can also do searches in Chinese, although China's "firewall" of Internet filters blocks many users from opening up the results.
"The general tendency over the past year has been to accuse foreigners of having a Cold War mentality and being anti-China," said Rebecca MacKinnon, an expert on the Chinese Internet at the Open Society Institute.
"How exactly they are going to react to this, I cannot anticipate, but it's likely that it will not be pretty."