PARIS -- The French government made a gesture of conciliation to striking French teachers on Monday, a day ahead of nationwide protests against pension reform that are expected to wreak more havoc in transport and public services.

At a meeting with teaching unions, Education Minister Luc Ferry and Interior Minister Nicolas Sarkozy offered to postpone a contested decentralization bill until after more negotiations have taken place later this year.

"Our discussions were relatively interesting. We were finally told that are worries were being heard. It is a step forward," said Gerard Aschieri secretary general of the FSU union. However he went on: "But we do not know where this is going to lead. Now is not the moment to take the foot off the accelerator. Far from it. The change in the government's tone was caused by the strength of our movement."

After waging an eight-month campaign against the government's center-right education policies, France's 800,000 teachers have taken the vanguard in recent public sector protests across the country, adding the pensions issue to their list of grievances.

Prime Minister Jean-Pierre Raffarin's tactic appeared to be to detach the teachers from the wider campaign by giving ground on one of their key complaints -- which concerns the transfer of authority in non-teaching parts of the educational system to the regions.

But teachers were set to join a mass day of strikes and demonstrations today intended to force Raffarin to withdraw the pensions reform bill which goes before Parliament next week. Many classes were expected to shut for the 10th time since the start of the school year.

Travelers were warned to expect severe disruption, with air, rail, bus and metro services all to be hit.

For the second time in a week, some 80 percent of flights to and from France were to be canceled because of a strike by air traffic controllers. Two of their unions have called for the stoppage to be extended into tomorrow and Thursday, although it was not clear if the disruption would be maintained.

Air France -- also hit by a strike by personnel -- said it could assure all long-haul flights but only 35 percent of shorter hauls. British Airways said it expected to cancel around 90 of its normal 120 daily French flights.

Only one train in three on average was due to run, with six rail unions starting their industrial action on Monday evening. However the Eurostar Service to London and the fast Thalys link to Cologne and Amsterdam were expected to operate as normal.

Paris commuters also faced delays with members of the hardline CGT union on the metro system preparing to walk out from Monday evening. But other unions were continuing to work after receiving assurances that their special pensions regime would not be affected by the government's plans.

Other strikes were planned by government officials, lorry drivers, dock workers, post and telecommunications staff, journalists, bank and shop staff, and workers in the chemical and metallurgical industries.

Backed by President Jacques Chirac, Raffarin's center-right government has so far ruled out renegotiation of the pension package, which was drawn up after months of talks with unions and business leaders and will go before the national assembly on June 10.

The bill is intended to ensure that the country's "pay-as-you-go" pensions system survives demographic pressures in the years ahead as the baby-boom generation ages. Its main provision is to make people work longer to get a full pension. The proposals have been described as a step in the right direction by the Organization for Economic Cooperation and Development (OECD) and accepted by France's second largest union. But two large public sector unions CGT and FO are spearheading street protests with the support of the political left.