The Chinese government has issued strict rules on "harmful" internet videos, after blocking access to YouTube over a clip purportedly showing police beating Tibetan independence protesters.

China's State Administration of Radio, Film and TV posted revised restrictions banning online videos that "oppose the basic principles of the Chinese constitution; jeopardize China's unity, sovereignty or territorial integrity, divulge state secrets; and endanger national security or harm national honor and interest," reports the Hollywood trade pub Variety .

Authorities have also barred online videos that "advocate evil cults and superstitions," or "explicitly display sexual perversions, extreme violence or the slaughtering of animals."

Furthermore, no movie or television show can be posted or downloaded that hasn't been approved to be shown in China. The People's Republic only allows a maximum of 20 foreign films (generally only blockbusters) a year - and usually after heavy editing.

The tighter restrictions are suspected to be a response to a video released on YouTube last month by the government of the exiled Dalai Lama allegedly showing Tibetan protesters being shackled and beaten by police during protests near Lhasa last March.

Chinese authorities have claimed the video is a fake and won't confirm the government was responsible for shutting off YouTube.

The government recently launched a nationwide crackdown on "lewd" and "obscene" internet content that has seen more than 1,900 websites blocked by authorities and at least 41 people detained. ®