At six am next Monday, the sound of church bells will sound the revolution in the South Pacific.

Shortly afterward, the revolution will arrive with its own sound track – the screeching of brakes, the crunch of metal on metal and screams of abuse as Samoan drivers start driving on the other side of the road, the first people in the world to make such a change since the 1970s.

Protests against the plans have seen up to 30,000 people - a sixth of the 180,000 total population - take to the streets. Legal challenges have got as far as the Supreme Court. But the Samoan Government will go ahead with its plan to force drivers to switch from driving on the right hand side of the road to the left.

A last ditch appeal to delay the changeover was rejected yesterday after Prime Minister Tuilaepa Sailele Malielegaoi convened a special Cabinet meeting to consider the request. After the meeting Mr Tuilaepa said that the date would remain September 7, despite predictions of chaos.

Samoan roads, poorly surfaced and badly maintained are a challenge to drivers at the best of times. Critics said that the change would mean confused drivers swinging out of their front gates straight into other cars, and pedestrians run down after forgetting which direction cars are coming from.

"Many preparations have been carried out," Mr Tuilaepa said in a statement. "A repeated request to government from the wider public has been to start the switch on the scheduled date to make it quicker for the country to become familiar to the changes."

There are strong econonic reasons for the Government's decision to bring drivers into line with Australia and New Zealand, a plan that has been in the pipeline for well over a year.

Instead of continuing to import expensive American-made left-hand-drive cars, Mr Tuilaepa and his ministers are keen to encourage some of the 170,000 expatriate Samoans living in Australasia to ship used cars back to relatives, lowering vehicle prices for the population of 180,000.

But opponents accuse the Government of trying to push the law through without properly preparing roads or its own population for the changeover.

Tole'afoa Solomona Toa'iloa, a New Zealand-educated lawyer who headed the legal challenges against the switch, said: "So we just wake up one morning and pull out of our driveways on to the other side of the road, do we? Cars are going to crash, people are going to die, not to mention the huge expense to our small country.”

The Engineers' Association of Samoa has estimated that the change will cost Samoa around 1 billion tula (£24 million).

The switch, which had been planned for July 2008, has already been delayed for a year but Mr Toa’iloa and the protest group People Against Switching Sides (PASS) claim that Samoa is still not ready. PASS president Lefau Waikaimoana So'onalolole said that the group accepted the inevitability of the changeover, but warned that necessary road works had not been completed.

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