Saboteurs staged a coordinated attack on France's high-speed rail network early on Wednesday, causing nationwide delays to services already hit by an eight-day transport strike, the SNCF state railways said.

The pre-dawn attack on signaling connections targeted the four main TGV train services out of Paris before government, management and unions resumed negotiations on ending the dispute over pension reform.

A senior SNCF executive blamed militant strikers for the damage and President Nicolas Sarkozy called for crack police teams to be dispatched to hunt down the culprits.

Those responsible for these acts of sabotage no doubt believed they could interrupt the negotiations and the return to work that is under way at the SNCF, Prime Minister Francois Fillon told parliament.

Well, I'm telling them they are very much mistaken.

Unions condemned the attacks and said there was no proof any of their members had been involved.

The pensions showdown is the biggest challenge Sarkozy has faced since taking office in May and his government fears its credibility would be destroyed if it gives in to the unions.

Only a minority of railway workers remained on strike, with the SNCF reporting that 77.2 percent of its staff had turned up to work on Wednesday against 73 percent on Tuesday.

The SNCF said it hoped to run two out of three high-speed TGV trains on Thursday, an increase on past days. Services on suburban trains and Paris's metro remained disrupted.

SEEKING COMPROMISES

Government, unions and management started negotiations at SNCF and the RAPT Paris transport company, which has also been seriously affected by the strike.

Unionists vote on Thursday to decide whether to continue the strike. But there was little hope of a definite resolution until the middle of December and Didier Le Reste, head of the powerful CGT union's rail division said the talks would take time.

It's not Didier Le Reste who's going to decide, he told reporters before the meeting. There'll be democratic debates in the local committees, he said.

Sarkozy said on Tuesday he would not renounce the core element of his pension reform, which entails an end to early retirement rights for transport and energy workers, but indicated he was ready to make concessions in other areas.

The head of France's business lobby said on Wednesday the dispute was causing incalculable damage to the economy.

An opinion poll published in the conservative Le Figaro newspaper on Wednesday gave Sarkozy a boost, saying 68 percent of people thought the transport strike was not justified.

The last time a government tried to reform the pension privileges was in 1995, but it had to backtrack in the face of nationwide stoppages and public sympathy for the strikers.

In a separate dispute, teachers, postal workers and civil servants returned to work after a one-day strike on Tuesday called to protest against the government's economic program. They have promised further stoppages in the months ahead.

Tobacco shop owners also took to the street on Wednesday, protesting against a smoking ban in bars due next year and many universities were disrupted by protests over education reform.