Eurostar train services from Paris to London and all trains heading from Paris Gare du Nord to northern France will also be suspended until midnight tonight.
"Due to an object on the tracks near Paris Gare du Nord, we are expecting disruption to our services this morning. Please change your journey for a different date of travel," posted Eurostar company on its X account this morning.
Workers found the explosive device near the tracks, about 2.5 kilometres from the station. Special squads of the Paris police are trying to secure the bomb.
There were crowds of people in the station hall, including many families who wanted to go on holiday.
North Station is the largest station in France, with TGV trains and Eurostar trains to the UK and other trains to Belgium departing from here.
