Google Inc. (GOOG) said Friday it was "taking all necessary steps" to block pornographic images and content from reaching users of its Chinese service, a day after the company was warned about pornography available through its search engine.

The Mountain View, Calif.-based company said in a statement it has met with Chinese government representatives to discuss problems with the company's Chinese service, through which pornographic images and content have been available based on foreign language searches.

Google was admonished late Thursday for the third time this year by a government-backed Internet regulator for "disseminating large amounts of pornographic and vulgar information."

It was not immediately clear, however, whether Google had been ordered to suspend search services for foreign Web sites via its Chinese Web site, as reported by the official Xinhua News Agency on Friday.

One Google spokesman said he was unaware of any request to suspend search activities and the company declined further requests for clarification.

"We are undertaking a thorough review of our service and taking all necessary steps to fix any problems with our results," the company said in a statement. "This has been a substantial engineering effort, and we believe we have addressed the large majority of the problem results."

The move is the latest effort by Chinese authorities to clamp down on online pornography, which has remained widely available to Chinese Internet users. Pali Capital analyst Tian Hou said the government has so far this year shut down as many as 2,000 porn sites hosted on servers in China.

The government recently caused a stir when it announced that all PCs sold in China would soon be required to carry pre-installed filtering software designed to block pornography and other content inappropriate for children.

Authorities have claimed the main targets of the so-called Green Dam-Youth Escort software are pornography, online gambling, and other sites deemed harmful to society, but critics fear that it could be used to detect and blocking sensitive political content.

With an online population of 298 million users, China already operates the world's most extensive Internet filtering system, commonly called the Great Firewall, which blocks access to pornography and politically sensitive sites, including those promoting Tibetan independence and the spiritual group Falun Gong.

Google has struggled to expand in China, where homegrown Baidu Inc.'s (BIDU) search engine controls about 60% of the market. Baidu has been the target of Chinese censors in the past, but wasn't mentioned in the latest crackdown on Google.

Standard & Poor's equity analyst Scott Kessler said the crackdown underscores the considerable challenges Google faces in China. "We view this as a notable risk," he said in a note.

-By Scott Morrison, Dow Jones Newswires; 415-765-6118; scott.morrison@dowjones.com; and Aaron Back, Dow Jones Newswires; (86-10) 6588-5848; aaron.back@dowjones.com