Venezuelans were woken before dawn yesterday by fake cannon fire, sirens and bugles as the Government tried to get them out of bed and to the polls so that they could give President Chávez sweeping new powers.

The alarm call came as Mr Chávez faced the toughest electoral fight of his nine-year presidency, with his efforts to overhaul the constitution on a knife-edge. Government workers had been pressed to vote “yes” to the changes, and Mr Chávez had warned poor Venezuelans that his popular health and education programmes would be at risk from a defeat.

“There is no middle ground,” he had told followers, some of whom were uncomfortable with his latest reforms. “Whoever votes against the referendum is against me.” The turnout was reported to be high, and voting was peaceful, despite violent protests leading up to the referendum.

Mr Chávez’s second rewrite of the Constitution since 1999 would, among other things, free him from presidential term limits, scrap the autonomy of the central bank and give him control over foreign currency reserves, swelled by soaring oil revenues. Mr Chávez, 53, has a mandate to remain in power until 2013, but he said that he was prepared to remain until 2050.

In a drive to transform the world’s fifth-largest oil exporter into a “socialist republic”, the new Constitution would allow the expropriation of private assets and introduce new forms of communal property. It would also grant Mr Chávez broad special “emergency” powers , including state censorship of the media. There are sweeteners, including cutting the working day from eight hours to six, extending social security benefits to informal workers, such as street vendors, and lowering the voting age to 16.

Theformer paratroop commander won a resounding reelection victory a year ago. Since then, however, a large student opposition has sprung up, sparked by his decision to close one of the few privately owned TV channels. With his own supporters more concerned about soaring crime, inflation and food shortages, Mr Chávez had reason to fear they might not have turned out in the numbers he needed.

In the lead-up to the vote, Mr Chávez engaged in diplomatic dog-fights with countries such as Colombia and Spain to stir up his supporters. On Saturday he invoked his traditional enemy, the US, casting the vote as a contest between himself and the US President. “Whoever votes ‘yes’ is for Chávez,” he said. “Whoever votes ‘no’ is voting for George W. Bush.”

Mr Chávez accused the US of plotting to discredit his victory at the polls. Any sign of meddling from Washington and he would cut off oil supplies to the US, he said. Mr Chávez has previously threatened to cut off oil supplies to the US, which gets about 15 per cent of its supply from Venezuela. But the threats are considered empty rhetoric by traders because few countries outside the US have the ability to refine Venezuela’s low-quality crude oil.

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