Websites in China censored President Barack Obama's references to communism and dissent in his inauguration speech and state television abruptly turned away from the broadcast once communism was mentioned.

Communist China has shut more than 200 websites in recent days for "vulgar" content, a move seen by many as another step in its battle to stifle dissent in a year of sensitive anniversaries, including the 20th anniversary of the bloody crackdown on the pro-democracy Tiananmen Square protests in 1989.

"Recall that earlier generations faced down communism and fascism not just with missiles and tanks, but with sturdy alliances and enduring convictions," Mr Obama said in his 18-minute inauguration address.

He later added:

"To those who cling to power through corruption and deceit and the silencing of dissent, know that you are on the wrong side of history, but that we will extend a hand if you are willing to unclench your fist."

After the Chinese translator said the word "communism," the China Central Television feed went briefly silent, then shifted to an anchor who stumbled through a question to an analyst about what type of difficulties Mr Obama faced with the US economy, according to an extract uploaded to Youtube.com.

The analyst looked equally caught off-guard.

In the text translations available on top Chinese internet portals Sina and Sohu yesterday, the word "communism" is omitted and the paragraph on dissent was gone.