The plans have sparked huge protests

Prime Minister Jean-Pierre Raffarin wants a series of changes which will mean workers having to pay into pension funds for longer to claim a full retirement rate.

Unions are staging a major campaign of strikes and protests against the plans, including a one-day air traffic controllers' strike on Tuesday, which grounded 80% of French flights.

Schools have also been badly hit.

More stoppages are planned, including an indefinite Paris transport walk-out starting at 2200 (2000GMT) on 2 June.

It is our generation's responsibility and our obligation to take the necessary steps Jacques Chirac French President

Teachers are meeting later on Wednesday to decide whether to call further strikes.

French President Jacques Chirac publicly backed the changes - which he called urgent and just - after Wednesday's cabinet decision.

"Without quick reform, pensions will run out of money as a result of the sharp increase in the number of retirees," Mr Chirac was quoted as saying by government spokesman Jean-Francois Cope.

Parliament

"It was the government's responsibility to act, and act promptly, in order not to have to take more brutal measures at a later date.

"For all French people, for all those whose future depends on the share-out pensions system, it is our generation's responsibility and our obligation to take the necessary steps."

The reforms now go before parliament. A vote in the National Assembly - the lower house of parliament - is expected on 10 June.

The pension system will collapse if we do not take the necessary measures Jean-Pierre Raffarin French Prime Minister

Mr Raffarin, leading a centre-right government, has said he wants his new law on the statute books by the time parliament starts its summer recess.

He insists the reforms are necessary because of the increasing number of people retiring and living longer, while the birthrate remains low.

The plans mean workers would have to pay into state funds for 40 years to claim a full pension - two-and-a-half years longer than at present.

The length of time would later be increased to 42 years.

Demographic 'stalemate'

Mr Raffarin, in a television address on Tuesday, said it was not reform but lack of reform which would jeopardise the rights of public sector workers.

France was facing "a demographic stalemate", he said.

"If we look to 2020 and beyond, we can see clearly that the pension system will collapse if we do not take the necessary measures and if we do not start the reform that the country expects," he said.

The shortfall in pension funds is expected to reach 50bn euros (�36bn; $57.4bn) by 2020.