A film of a man hitting a woman in the face in central Paris after she told him to “shut up" for harassing her in the street has shocked France and prompted an investigation.

Social media posts of Marie Laguerre on her ordeal have prompted outrage and a pledge by France's gender equality minister to start imposing on-the-spot fines for street harassment this autumn.

The 22-year old student was walking home in Paris’ 19th arrondissement last week when she was accosted by a young man at the terrace of a bar in broad daylight.

Marlène Schiappa, France’s gender equality minister, called the assault an attack on the "freedom of women" as she backed plans to introduce on the spot fines for harassment including wolf-whistling.

Describing her deal on social media, Ms Laguerre wrote in English: “I walked past a man who sexually/verbally harassed me."

“He wasn't the first one and I can't accept being humiliated like that, so I replied ‘shut up’,” she wrote.

“He then threw an ashtray at me, before rushing back to punch me, in the middle of the street, in front of dozens of people.”

She later told Le Parisien that he had insulted her repeatedly, wagged his tongue and made sexually suggestive "groans".