France's interior minister has pledged to beef up security on the country’s Alpine borders with Italy after a far-Right "commando" blocked access to migrants seeking to cross a key snowy pass, and pro-migrant groups stormed another entry point.

The pledge came hours after France's National Assembly passed a controversial immigration law that laid bare unprecedented splits in President Emmanuel Macron's ruling centrist party.

Late Saturday and early Sunday, a group of around 100 activists from the small far-Right group Génération Identitaire - reportedly including Britons - launched a high-profile attempt to shut off the col de l’Echelle, a 1,762m-high pass some six kilometres (almost four miles) from the Italian border.

They erected makeshift barriers at the “strategic point for illegal immigrants” and unfurled a banner in English which read: “Closed border. You will not make Europe your home. No way. Back to your homeland.”

Pro-migrant groups responded to the operation by forcing a passage at the nearby Montgenevre Pass, taking around 30 migrants with them from Italy to France after scuffles with French border police. Two pro-migrant activists were arrested on Monday.