The last-minute strike was announced on Thursday evening and is over safety concerns following an accident, say unions.
In Paris this is affecting the RER suburban trains, which are run by SNCF. These connect Paris to the suburbs and also the city's main airports to Gare du Nord.
“Following an unexpected industrial action, traffic is very disrupted throughout the line,” explained SNCF.
? 6h06 #RERD
A la suite d'un mouvement social inopiné, le trafic est très fortement perturbé sur l'ensemble de la ligne.
— RER D SNCF (@RERD_SNCF) October 18, 2019
The Metro, which is run by RATP, is not affected.
In Lyon no trains are leaving from Perrache and there are limited services from Part-Dieu while regions across the country have seen delays and cancellations to the TER local services network.
Due to the last-minute nature of the strike, there will be changes throughout the day as SNCF struggle to provide a service – passengers are advised to either postpone their trip or check on the SNCF website for disruptions ahead of travel.
Although there have been several strikes recently over the ongoing issue of pension reform, this industrial action is not related to that, say unions.
The reason for the last-minute strike was given as safety concerns after an incident in Ardennes in eastern France.
A train carrying 70 passengers hit a lorry at a level crossing in Saint-Pierre-sur-Vence.
The CGT union said the incident could have had “dramatic consequences”.
A union official told Le Parisien: “The driver was alone and isolated and had to handle a multitude of regulatory procedures and manage users, including several pregnant women, all in a state of shock.”