Residents prayed for calm as Samoa prepared Monday to become the first country in nearly 40 years to switch driving from one side of the road to the other.

Critics have predicted traffic chaos in the Pacific island nation of 180,000, and the country is banning alcohol sales for three days as a precaution, the prime minister said.

The switch from driving on the right side of the road to the left takes effect from 6:00 a.m. Monday (1 p.m. EDT Monday). It is being ushered in with a two-day national holiday to reduce traffic.

The Congregational Christian Church of Samoa, the country's largest denomination, offered blessings Sunday to help the switch go smoothly.

"It's a must „ people have to be blessed before we come to the changes," said the Rev. Iutisone Salevao.

The government wants to bring Samoa in line with Australia and New Zealand to encourage some of the 170,000 expatriate Samoans there to ship used cars, with steering wheels on the right side, home to relatives.

Opponents, however, have accused the government of pushing the change through without adequately preparing drivers.

Prime Minister Tuilaepa Sailele Malielegaoi said the government has already widened roads, added new road markings and signs and installed traffic-slowing speed humps on key roads on the nation's two main islands of Upolu and Savai'i.

"The time is right for us," he said Sunday. He had driven on the left in London and "it took me only three minutes and I knew how to maneuver," he told Television New Zealand.

The government will continue to allow vehicles with left-side steering wheels after the changeover.

Samoa will be the first country in decades to switch the flow of traffic. Iceland and Sweden did it in the 1960s, and Nigeria, Ghana and Yemen did it in the 1970s.

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