Transport chaos is expected in France today as the country enters a trial of strength between President Sarkozy and public sector workers who are going on strike over pensions.

The outcome of the indefinite action by national railway and Paris transport workers will seal the fate of the more radical medicine that Mr Sarkozy promised to administer to France in his election campaign last spring. “It is by vanquishing the street that Sarkozy will win or lose his ability to deepen reforms and put in place the clean break that he announced more than a year ago,” Le Figaro said.

The only train service due to run normally is the Eurostar, which opens its new 2 hour 15 minute link between London, St Pancras and the Paris Gare du Nord this morning. Police are deployed near the station to prevent disruption by pickets or students who have mounted a broad “antiSarko” movement and fought antiriot squads in three universities yesterday.

As travellers cancelled journeys and commuters prepared for days of disruption, cycling, car-pooling or staying at home, Mr Sarkozy warned the trade unions that he would not surrender, as previous governments had done.

“I will pursue these reforms to the end,” he told the European Parliament. “Nothing will blow me off course. The French people approved these reforms. I told them all about it before the elections so I would be able to do what was necessary,” he said.

Mr Sarkozy, nicknamed the Hyper-President, is counting on solid public backing, but is worried about the darkening mood in the country six months into his five-year term. The French are feeling less well-off than ever despite his promises to unleash growth with summer tax cuts. A poll for Libération found that 79 per cent believed that he had so far failed to meet his central economic pledge. Some of his aides are reported to be blaming one another for bungled economic decisions in the early months.

Mr Sarkozy was, however, comforted by polls that show about 55-60 per cent of voters against the strikes, which are being waged to save early retirement schemes. This support contrasts with majority backing for the strikers who defeated President Chirac’s government in the last big shutdown, over the same pensions issue, in 1995.

Leaders of the mainstream trade unions are uneasy about alienating opinion with strikes that are being driven by Trotskyite and other hard-core leftwingers. Most concede privately that the early retirement of rail, energy and other public sector workers can no longer be sustained and that their conditions must be aligned with those of the civil service. They blame Mr Sarkozy for failing to offer enough sweeteners. The opposition Socialist party agrees, though François Hollande, their leader, accused Mr Sarkozy of provoking the strikes.

The union hardliners, such as Christian Mahieux of the militant Sud-Rail union, are drawing strength from residual sympathy for the workers in France’s ancient class wars. Mr Mahieux said that his goal was the defeat of the whole Sarkozy reform programme. “The Government will have no choice but to cede and withdraw its [pensions] proposal,” he added.

At stake in the strikes are the early retirement terms of 500,000 workers in transport, energy, the merchant navy and the Paris opera and other state theatres. The pensions are at present costing taxpayers €5 billion (£3 billion a year) to subsidise.

Teachers, hospital and post office and other state staff, whose pensions were reformed in 2003, are to strike on November 20 against Mr Sarkozy’s plans to trim the civil service. The rail strikes may last until then, although services are expected to resume as members of moderate unions return to work by the weekend.

Unrest at the universities has sparked disputes between militants who want to “bring down the Sarkozy administration” and apparent majorities of students who are opposed to disruption. The focus of the protests is a reform that will allow universities, which are chronically neglected and underperforming, to charge fees and accept donations from business.

In Nanterre, western Paris, students clashed with riot police who fired tear gas and forced open doors, though classes remained cancelled.

How the campaign will be waged

From today until further notice

— On the national SNCF railways, only nine out of 700 high-speed express trains (TGV) will run

— Thirty intercity expresses will run

— No commuter or regional train services will run

— The Eurostar link with London St Pancras should operate normally

— The Thalys service to Brussels and the Netherlands will have 30-minute delays

Paris

— The RATP bus, underground and tram system will run about one in ten services, with traffic normal only on underground line No 14

— The Government is advising people to delay journeys at least until the weekend. With transport around Paris and on railways out of action, travellers will have to use taxis, buses, hire cars and bicycles

— Most of the 15,000 vélib self-service bicycles of Paris are likely to be hired early in the day

Power supplies

— Workers at EDF and GDF electricity and gas utilities are also on strike

Entertainment

— The Opera de Paris and Comédie Française are on strike today and November 22

November 20

— There will be a strike by teachers, students, school pupils, post office workers and France Télécom staff

November 29

— Justice Ministry employees will strike over plans to close rural law courts

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