Borat, a mockumentary featuring a fictional Kazakh reporter, is the number one film at the UK and Ireland box office.

The movie, starring British comedian Sacha Baron Cohen as Borat, took £6.2m in its opening three days, Screen International said on Tuesday.

The previous number one, gory horror film Saw III, fell one place to second.

Step Up, the dance-based romantic drama starring Channing Tatum, took third place, with Martin Scorsese's gangster movie The Departed fourth and Meryl Streep's fashion-themed comedy The Devil Wears Prada fifth.

Helena Bonham Carter’s comedy Sixty-six debuted at number eight, while Kate Winslet’s crime drama Little Children entered the UK chart in tenth place.

Borat - full title Borat: Cultural Learning of America for Make Benefit Glorious Nation of Kazakhstan - has also performed well at the US box office.

The film generated an impressive $26.4m (£13.9m) as it went straight to number one over its opening weekend.

This Friday sees the release of The Prestige, a magical thriller starring Scarlett Johansson, and Breaking and Entering, a romantic drama about a landscape architect who falls in love with a young thief.

Directed by Christopher Nolan, who made Batman Begins, The Prestige also features Christian Bale, Hugh Jackman and Michael Caine.