A police helicopter and 60 riot police deployed Saturday in central Marseille to prevent any protests about anti-Islam cartoons, but only a single demonstrator turned out.

Around 30 journalists were also on hand to witness the man's attempt to defy an official ban on protests about a French magazine that published cartoons mocking the Prophet Mohammed.

"I may be the only one today but I am the spokesman of a silent majority," Omar Djellil, whose request to hold a legal demo was turned down by police, told reporters as he harangued passers-by from atop a concrete block.

Djellil proceeded to stick posters on nearby walls in the southern port city that read "Hebdo Pigs" and "French Muslims don't need authorisation to defend their rights".

"Hebdo Pigs" was a reference to the satirical weekly Charlie Hebdo, which on Wednesday published cartoons of a naked Prophet Mohammed.

A police source said there was no question of arresting Djellil, especially as he was on his own.

French Interior Minister Manuel Valls had said he would not sanction any protests this weekend on the grounds they would inevitably represent a threat to public order.

Riot police were deployed in several areas of Paris Saturday to enforce the ban on protests over the cartoons and over a film mocking the Prophet Mohammed that has enraged Muslims around the world.

By mid-afternoon, there were no reports of anyone trying to protest in the capital.