In April, the government of Ile-de-France commissioned a 10-member panel of experts led by Mr Jacques Rapoport, former president of infrastructure manager SNCF Network to examine the feasibility of abolishing all fares for local public transport in the region.

The study concludes that free travel would result in an immediate 6-10% uplift in public transport ridership, which would have a detrimental impact on service quality across the network.

Furthermore, the transition to free public transport would require €2.2-3.3bn in additional funding.

Ile-de-France Mobility says free travel is not sustainable given the need to bring the network up to modern standards, with investment of €25bn flowing into the system by 2025.

More than 1 million people already benefit from free travel or reduced fares in the region and Ile-de-France Mobility says making access to the network completely free would not improve social equity as those who can most afford to bear the price of transport would benefit most.