'No confidence' in French PM, government near collapse

The French government is all but certain to collapse later this week after far-right and left-wing parties said they will vote for a no-confidence motion against Prime Minister Michel Barnier.

Their move came after Barnier said he would try to ram a social security bill through parliament without a vote as a last-minute concession was not enough to win support for the bill from the far-right National Rally (RN).

RN leader Marine Le Pen said her party would table its own no-confidence motion but will also vote for any similar bill by other parties.

"The French have had enough," she said on Monday.

"Maybe they thought with Michel Barnier things would get better, but they were even worse."

Mathilde Panot, of the hard-left France Unbowed, said: "Faced with this umpteenth denial of democracy, we will censure the government...We are living in political chaos because of Michel Barnier's government and Emmanuel Macron's presidency."

Should all RN MPs vote with the left to topple Barnier, the government will not survive.

Barnier's struggles to get the 2025 budget through a deeply divided parliament threaten to plunge France into its second political crisis in six months, underlining the instability that has taken hold in countries across the EU.

He urged MPs not to back the no-confidence vote.

"We are at a moment of truth," Barnier told parliament as he put his government's fate in its hands.

"The French will not forgive us for putting the interests of individuals before the future of the country."

The opposition now has 24 hours to put forward a no-confidence motion. The vote could take place as early as Wednesday. No French government has been forced out by such a vote since 1962.

Since its constitution in September, Barnier's minority government has relied on RN support for its survival. The budget bill, which seeks to rein in France's spiraling public deficit through 60 billion euros ($A97 billion) in tax hikes and spending cuts, may snap that tenuous link.