Praying in the streets of Paris is against the law starting Friday, after the interior minister warned that police will use force if Muslims, and those of any other faith, disobey the new rule to keep the French capital's public spaces secular.

Claude Guéant said that ban could later be extended to the rest of France, in particular to the Mediterranean cities of Nice and Marseilles, where "the problem persists".

He promised the new legislation would be followed to the letter as it "hurts the sensitivities of many of our fellow citizens".

"My vigilance will be unflinching for the law to be applied. Praying in the street is not dignified for religious practice and violates the principles of secularism, the minister told Le Figaro newspaper.