Trains were only scheduled to run between London and Lille, before a limited bus service is offered to take travellers on to Belgium.
High-speed rail connections from Brussels to destinations in France, the Netherlands and Germany are likely to be hit as well. Eurostar services between London and Paris will run normally despite the wave of strikes to have hit France and are set to continue this week.
President Nicolas Sarkozy wants to up the retirement age from 60 to 62 and the full state pension age from 65 to 67.
He says the reforms are needed to stop the country’s Ã¢â€šÂ¬32billion (Ã‚Â£28billion) annual pension shortfall increasing to Ã¢â€šÂ¬50billion by 2020.
But unions are predicting millions will again take to the streets. Fuel stocks are beginning to be hit by panic buying after refineries were blockaded by workers striking at ten of the country’s 12 refineries.
In Marseille, rubbish is piling up amid an on-going strike by bin collectors. Police clashed with masked protesters in the city and in Paris over the weekend as tensions bubbled over.