The far-right leader holds the fate of the country’s government in her hands, as a battle royale over the national budget reaches its denouement and investor anxieties rise.

Barnier warned that toppling the government could cause a "big storm and very serious turbulence" in financial markets. Some analysts believe that France is heading for a debt crisis reminiscent of the near implosion of the eurozone in 2012, when Greece was forced to seek a bailout from the EU and International Monetary Fund.

To survive the vote in the fractured lower house, Barnier needs Marine Le Pen's party to abstain, otherwise his government and the budget bill could fall, plunging France into a political crisis.

French Prime Minister Michel Barnier's government faces a major test over approval of a disputed draft budget, with far-right leader Marine Le Pen threatening a no-confidence vote in parliament should its budget demands not be addressed.

French Prime Minister Michel Barnier must make further budget concessions to avoid a no confidence motion that could topple his government, National Rally lawmaker Marine Le Pen said on Sunday. Le Pen has given Barnier until Monday to yield to budget demands from the National Rally (RN) or face the threat that they would back a likely no confidence motion against his government,

The French government “has put an end to discussions” on possible changes to the social security bill, Marine Le Pen told AFP on Sunday, paving the way for a possible no-confidence vote as soon as Wednesday.

Marine Le Pen, National Rally (RN) leader, has threatened to bring down the French government on Monday if Michel Barnier, France’s prime minister, does not drop effective cuts to pensions.