On the eighth day of a transport strike in France, the state-owned rail operator, SNCF, has accused militant unionists of conducting a "concerted campaign of sabotage".

An SNCF statement said there had been several simultaneous incidents, including a number of fires, aimed at stopping the resumption of services on the high-speed network.

The incidents have been condemned by both the government and union officials. President Nicolas Sarkozy said the saboteurs would be severely punished.

Talks have now begun between most of the main rail unions, managers and government officials to end the strike which is over proposed changes to the pension system.

The French government last tried to overhaul "special" pensions in 1995. The move sparked three weeks of strikes that forced then-President Jacques Chirac to climb down.

On Tuesday, Mr Sarkozy said in a speech that the economic reforms were overdue and necessary "to confront the challenges set by the world".

Before the latest incidents, the SNCF had estimated there would be slightly improved rail services on Wednesday as the number of strikers steadily declined.

The strikes have caused havoc for millions of commuters across France. Businesses have started complaining that the strikes are hurting their operations.