Scores of domestic and European flights were cancelled, including all Ryanair flights to France, thanks to action by air-traffic controllers. In the northern port of Calais, ferries for Dover were prevented from leaving the quayside.

In a bid to defuse the protests, M Chirac agreed on Friday to change the CPE’s two most contentious provisions: reducing the two-year probationary period to one year and requiring employers to provide some written reason for dismissal.

But the student protesters, clearly relishing their success so far, say that they will continue demonstrating until the law is ditched altogether.

"What Chirac has done is not enough," said 18-year-old Rebecca Konforti, among a group of students blockading a high school in southern Paris today. "They’re not really concessions, he just did it to calm the students."

Charles Bremner, Paris Correspondent of The Times, said that the protesters were clearly lifted by M Chirac's U-turn. "This is the protesters' victory lap," he said. "The schoolkids are still enjoying their spring revolution, but the political cause behind it has been defused. Chirac has caved in."

He added: "It's all over bar the shouting."

Union and student groups said that marches and demonstrations were planned in nearly 200 towns and cities, from Nantes in the west to Saint-Etienne in the southeast. One of the largest was in the Mediterranean port of Marseille, where union figures put the number of protesters at 250,000. There was even a demonstration in the French Indian Ocean island of Reunion.

In a sign of the shifting balance of power in the Cabinet, responsibility for amending the CPE was taken from M de Villepin and handed to M Sarkozy, his main rival as the Right's candidate in next year's presidential election.

Unions and student groups insisted that the Government had to abandon the CPE outright before negotiations could begin, but deputies from M Sarkozy's UMP party said that talks would begin from tomorrow and take place in the Senate building.

Bernard Accoyer, head of the UMP bloc in the National Assembly, said the agenda would be completely open. "There is no limit to our discussion. Everything is on the table. It is time to turn the page," he said.

Francois Chereque of the CFDT union added: "Sarkozy has told us he is willing to discuss everything with no taboos. Accoyer has said he is willing to hear our reasons why we want the withdrawal of the CPE. If this is the approach, then we will go to the talks."

But there is widespread anger on the Right not just that M Chirac has mishandled the crisis but that he has once again bowed to the power of street protests. Philippe de Villiers, a nationalist leader, accused M Chirac of giving in completely and said that the abrogation of the CPE would "seal the victory of violence, of government by riot".

Times Recommends

• It’s only Brits who don’t appreciate me, says Blair
• Party’s over for Greek graspers
• White House tightens security for Xmas marathon