Cars is the Pixar company's seventh animated feature

The film's three-day take of $62.8m (�34m) makes it the company's third most successful opening after The Incredibles and Finding Nemo.

Jennifer Aniston's comedy The Break-Up, last week's number one, fell to two.

The Omen, a remake of the 1976 horror classic which opened on 6 June, made $15.5m (�8.4m) at the weekend, taking its total US tally to $35.7m (�19.3m).

The film, released to coincide with 6/6/06, made $12.6m (�6.8m) on its first day of release, a record for a Tuesday.

'Sure thing'

Directed by John Lasseter, Cars tells the story of a hotshot race car forced to spend a week in a sleepy desert hamlet.

It is directed by John Lasseter (l) and stars Paul Newman (r)

The film, which features the voices of Owen Wilson and Paul Newman, opens in the UK on 28 July.

All of Pixar's other collaborations with the Disney studio have opened at the number one in North America.

"They are the closest thing to a sure thing in Hollywood," said Paul Dergarabedian of box-office analysts Exhibitor Relations.

Cars is the first Disney-Pixar feature not to outperform its predecessor on its opening weekend.

Robert Altman's A Prairie Home Companion - based on Garrison Keillor's popular radio show - was the week's other new release.

The film, which opened in 760 cinemas, entered the chart at seven with takings of $4.7m (�2.5m).