The Iranian government plans to permanently suspend Google Inc's email service in the country, the Wall Street Journal reported on its website on Wednesday.

Google said it experienced a sharp drop in email traffic in Iran, and that some users in the country were having trouble accessing Gmail, but said its networks were working properly.

The report comes as Iran braces for new opposition protests on Thursday during rallies marking the 1979 Islamic revolution. Protesters made use of modern networking tools such as Twitter and Gmail instant messaging last June after a disputed election plunged Iran into crisis.

Google is already at loggerheads with China's government after it threatened to withdraw from the country last month over claims of online attacks and issues over censorship.

Iran's telecommunications agency announced the suspension and said a national email service for Iranian citizens would soon be rolled out, the Wall Street Journal reported.

Google reported a drop in email traffic, but did not confirm the Journal report.

"We have heard from users in Iran that they are having trouble accessing Gmail," a Google spokesman wrote in an e-mail to Reuters. "We can confirm a sharp drop in traffic, and we have looked at our own networks and found that they are working properly."

He added that Google supported free online communication, but "sometimes it is not within our control."

There was no immediate comment from Tehran, where it was after midnight when the news broke. Opposition leaders have called on supporters to take to the streets on Thursday, raising the risk of renewed violence.

The US State Department could not confirm the report, but said any efforts to keep information from Iranians would fail.

"While information technologies are enabling people around the world to communicate ... like never before, the Iranian government seems determined to deny its citizens access to information, the ability to express themselves freely, network and share ideas," State Department spokesman P.J. Crowley said.

"Virtual walls won't work in the 21st century any better than physical walls worked in the 20th century."

Google Inc said it may create a stand-alone version of its Buzz social networking product but won't separate Buzz from its Gmail service, a linkup that has spurred controversy over privacy.

Google, the world's No.1 Internet search engine launched Buzz earlier this week in a bid to tap into the fast-growing social networking market dominated by companies like Facebook and Twitter.

Buzz allows users to broadcast messages and share photos and videos with friends and colleagues online, similar to Twitter and Facebook. But unlike those services, Buzz is built directly into Google's Gmail and the product automatically creates each users' social network based on the person's most-frequently emailed contacts.

"We have considered, among all the other features that we add to Buzz in the future, to create a stand-alone experience in addition to it being in Gmail," Google spokeswoman Victoria Katsarou told Reuters on Friday.

In the days since the product launch, a number of online blogs and publications have argued that the Buzz-Gmail link creates a privacy problem since the Buzz contact network is publicly viewable by default and could expose people's private contacts.

On Thursday, Google announced a couple of changes on its corporate blog designed to address some of the concerns, including making it easier for Buzz users to keep their contacts list private.

The blog Search Engine Land quoted Google Vice President of Product Management Bradley Horowitz as saying the company was considering removing Buzz from Gmail, but Google's Katsarou said that that was not the case and the blog later reported that Buzz would remain in Gmail.

Google also said in its blog post on Thursday that more than 9 million posts and comments have been created on Buzz since its launch and that tens of millions of people have "checked Buzz out."

Gmail is the world's third most popular Web email service, with 176.5 million unique visitors in December, according to comScore, behind Microsoft Corp's Windows Web email services and Yahoo Inc's email.