French Prime Minister Michel Barnier is bracing for a no-confidence vote this week, a political reckoning poised to topple his fragile government and send shockwaves across the eurozone.

PARIS—Anti-immigrant leader Marine Le Pen is engaged in a high-stakes game of chicken with the French government and a multitude of global investors who finance the country’s sizable debt load.For weeks,

French Prime Minister Michel Barnier used a constitutional tool to push through parts of his unpopular budget bill without a parliamentary vote, raising the prospect lawmakers could dissolve his government within a matter of days.