By Will Grant BBC Americas editor, Miami

Mr Chavez's supporters gathered outside the National Assembly

Under the current rules, Mr Chavez would have to step down at the end of his second term in office in five years' time.

Following his re-election last year, by an overwhelmingly margin, Mr Chavez proposed key changes to bring about what he called a 21st Century socialist revolution.

Under those changes, he has nationalised key sectors of the economy, including telecommunications, electricity and important foreign oil installations in the Orinoco river belt.

He has proposed merging all the pro-government parties into a single political bloc and he has warned private health-care providers that he will nationalise them if they fail to bring down the cost of their services.

Referendum

The constitutional changes proposed in his speech on Wednesday included plans to increase presidential control over Venezuela's municipalities and states.

These reforms are intended to accelerate the push towards 21st Century socialism, with some observers speculating that further land reforms could be introduced.

The opposition have questioned the president's intentions, saying a new constitution was not needed as the current one was only drafted eight years ago.

They say the president's reasons are personal - motivated by a desire to strengthen his hold on power.

But any plans put on the table by Mr Chavez must go first to a national referendum.

If his recent performances at the polls are anything to go by, he is likely to fare very well among the voters.