Morales made implementing a new constitution a pillar of his agenda when he took office in 2006.

But his proposals have been opposed by several powerful regional governors who argue that the proposed constitution does not represent all Bolivians and have called the constitutional draft "racist" and "illegal".

'Let the people decide'

Bolivia's eastern regions have been the scene of much anti-Morales protests.

The gas-rich regions want greater autonomy from the central government and the return of energy revenues paid into a national pension fund.

Demonstrators in the regions have repeatedly have blocked airstrips to keep Morales away ana a block of opposition politicians governing five of the country's nine regions have vowed to boycott any referendum on the constitution.

Landowners in the east, where much of the country's farmland is located, are also angry at Morales' plan to expropriate fallow land that he says is used for "speculation".

The referendum will ask voters to decide how much land individuals should be allowed to own and to approve or reject the text of the new constitution.

Negotiations since the recall election, which took place on August 10, failed to end the political crisis.

"Let the people decide with their vote on the constitution," Morales said on Thursday night, "since we the authorities are unable to agree."

Legislators allied with Morales approved a constitutional draft late last year in an elected assembly, but the vote was boycotted by opposition delegates.