TEHRAN (Reuters) - Iran's supreme leader accused the United States Tuesday of trying to use the Internet as a tool to confront the Islamic Republic, declaring that such a policy only showed Washington's frustration.

Last week, U.S. Secretary of State Hillary Clinton challenged Beijing and other governments to end Internet censorship, placing China in the company of Iran, Saudi Arabia and others as leading suppressors of on-line freedom.

The Internet has become a battleground during domestic turmoil in Iran after June's disputed election, with the authorities blocking access to some opposition websites and pro-reform Iranians using it to spread word of new protests.

US President Barack Obama asked China to abandon the so-called practice of “internet censorship” during his China trip last month, calling for the freedom of expression and non-censored internet.

However, internet censorship is far from an issue of black and white. Even in Obama’s own country, whether to censor the internet or not is under intense debate.

Two federal laws intended to censor offensive online content were passed at the turn of this millennium, while four states -- New York, New Mexico, Michigan and Virginia have passed Internet censorship legislation restricting/banning online distribution of material deemed "harmful to minors" since 1996.

The Chinese Government has blocked access to Twitter, Hotmail and Flickr two days before the anniversary of the massacre in the Tiananmen Square.

This Thursday will be the 20th anniversary of the Tiananmen Square Massacre, when on June 4, 1989, the tanks entered the Square to crush protests by students and workers.

China has never made public the list of victims of what qualifies as a "counterrevolutionary conspiracy."

Social networking sites like Facebook could be monitored by the UK government under proposals to make them keep details of users' contacts.

The Home Office said it was needed to tackle crime gangs and terrorists who might use the sites, but said it would not keep the content of conversations.
It is part of a plan to store details of all phone calls, e-mails and websites visited on a central database.
Civil liberties campaigners have called the proposals a "snoopers' charter".

Tens of millions of people use sites like Facebook, Bebo and MySpace to chat with friends, but ministers say they have no interest in the content of discussions - just who people have been talking to.

Overkill

Liberal Democrat MP Tom Brake said the websites contained sensitive personal details and he was concerned information could leak from any government-controlled database.

By JESSICA E. VASCELLARO and GEOFFREY A. FOWLER

Access to GoogleInc.'s YouTube service was blocked by Chinese authorities, as the video-sharing site continues to wrestle with governments offended by some of its content.

A YouTube spokesman said as of Tuesday evening it hadn't been contacted by the Chinese government and was working to restore the service, which had been disrupted for more than 24 hours.

The site has been temporarily censored in at least a dozen countries, according to YouTube, including Turkey, where a ban remains in effect. Such incidents are buffeting YouTube's attempts to expand into new markets, particularly China, home to the world's largest number of Internet users—nearly 300 million, according to the government.

YouTube faces stiff competition in China from domestic video-sharing sites such as Tudou.com, which are less likely to get blocked in their entirety because they restrict political or racy content that might draw fire from the government.