French police fire tear gas in western city of Nantes-TV

French police fired tear gas at protesters in the western city of Nantes, the BFM news channel reported on Thursday, during one of the biggest public sector strikes for decades aimed at forcing President Emmanuel Macron's to abandon his pension reform plans.

Transport networks in Paris and cities across France ground to a near halt as unions dug in for a protest that threatens to paralyse France for days and poses the severest challenge to Macron's reforms since "yellow vest" protests erupted.

Before the start of a rally in Nantes some protesters threw projectiles at police, who responded with tear gas and arrests.