Internet companies including Yahoo and MSN have signed on to new government guidelines on blogging in China.  An international press-freedom watchdog says the pact will lead to censoring and silencing of those who post their words on computer Web logs.  Claudia Blume reports from VOA's Asia News Center in Hong Kong.

Yahoo, MSN and a number of Chinese blog service providers signed the so-called "self-discipline" pact at the end of last week.  The pact does not force, but rather "encourages" Internet companies to register and store the real names, addresses and other details of their users.

Beijing had earlier tried to implement legislation that would have made such registration mandatory, but the plan met with strong resistance from both Internet companies and the public.

Nevertheless, the Chinese authorities can now go to any company that stores such information in order to identify anyone posting material online.

Vincent Brossel of the press freedom group Reporters without Borders says the more cautious wording of the agreement will not protect Chinese bloggers.

"They have to 'encourage,' and everybody puts the word 'encourage' between brackets, because 'encourage' in China means you have to do it in some way, non?  ...  When the government wants this type of information they will be able to get it, because we know that in the past these companies, including Yahoo and MSN, have delivered information, I mean private information, about Internet users," Brossel said.

In 2005, Yahoo's China operations were taken over by Alibaba.com, a Chinese Internet company.  In an official company statement, Yahoo Incorporated says it understands that Alibaba does not "currently" plan to implement "real-name registration" of bloggers.

Prior to the link-up with Alibaba, Yahoo passed information about one of its Chinese users, journalist Shi Tao, to the Chinese authorities.  As a result, Shi was arrested, and in 2005 was given a 10-year jail sentence for divulging state secrets.

Shi and Wang Xiaoning, who was also jailed after Yahoo provided his confidential information to the authorities, are suing Yahoo in U.S. court. The suit seeks a court order to stop Yahoo from cooperating with Chinese requests for the identities of Internet users.

Brossel says the "self-discipline" agreement has been publicized in China, and that Chinese bloggers realize they will no longer be able to post items anonymously.

"So I think it will have a chilling effect, and it will increase self-censorship," Brossel said.

The blog service providers who signed the new agreement also pledged to monitor the comments posted by their users, and to delete in advance information the government does not approve of.

Rebecca MacKinnon is an expert on online media at the University of Hong Kong.  She says this is nothing new: Both Chinese and foreign companies, eager to stay in business in the world's second-largest Internet market, have long been censoring Chinese Web sites and blogs.

"The signing if this pledge really is only just making public what is already being practiced ...   In theory - according to the guidelines of the pledge - they will ask their users to acknowledge that this is happening and to agree that if you are going to have a blog here, we will censor you - that is life here in China!" MacKinnon said.

An estimated 30 million people in China write online diaries, or blogs, and their number is growing steadily.  Until now, bloggers could remain anonymous online using screen names, and in a country where the news media and personal expression are controlled, blogs have become an important forum for citizens to express and exchange views freely.  If the authorities can obtain their real identities from the service providers, this avenue for free expression is likely to be closed off.