Hollywood actor Ewan McGregor gave his daughter Clara free rein while filming the road movie You Sing Loud, I Sing Louder together.

"There wasn't any advice being thrown around: 'Do it like this' or 'Do it like that.' It doesn't really work like that," the British actor said on Sunday (July 2) at the Karlovy Vary International Film Festival.

In front of the camera and the audience, everyone is responsible, regardless of age and previous experience, the 52-year-old stressed. Acting is about finding the truth.

The US film You Sing Loud, I Sing Louder celebrated its foreign premiere in the Czech town of Karlovy Vary, which hosts one of the oldest film festivals in the world.

It is about a father who wants to take his daughter, who is estranged from him, to a rehab clinic after a drug overdose without her knowing about it.

McGregor, who has appeared in cult films such as Trainspotting, accepted the honorary award from festival president Jiří Bartoška on Saturday evening.

Already at the opening gala on June 30, Gladiator star Russell Crowe had been awarded the Crystal Globe for extraordinary services to world cinema.

To the delight of the young festival audience, the Oscar winner also performed with his band Indoor Garden Party - one of the musical highlights alongside the London band Morcheeba.

The 57th Karlovy Vary International Film Festival ends on July 8.

The film festival, which alternated with its Moscow counterpart until 1992, is one of the oldest in the world. It transforms the town in the west of the Czech Republic into a party stronghold for a few days.

Last year, more than 121,000 tickets were sold for film screenings. – dpa