France’s left-wing and centrist parties have withdrawn hundreds of candidates from Sunday’s parliamentary elections, in a move aimed at thwarting the formation of the country’s first far-right government since World War II.

The mass exit came before a Tuesday registration deadline before the final run-off vote on Sunday. The withdrawing candidates were mostly either allies of French President Emmanuel Macron or from left-wing parties.

Macron had called for snap parliamentary elections in June after his party was trounced in European elections, but the move appears to have largely backfired. Instead of shoring up the mandate of his centrist Renaissance party, Marine Le Pen’s far-right National Rally (RN) party won the most seats in the first round of voting on June 30.

Le Pen’s party, which espouses an anti-immigration platform with policies decried as Islamophobic, hopes to win enough seats in the second round of voting to form a government. Le Pen said on Tuesday the party will still seek to form a government even if it falls just short of the 289-seat absolute majority in the 577-seat National Assembly.

Macron’s centrists and the left-wing New Popular Front (NFP) hope they can prevent such an event, with the president telling a closed-door meeting of ministers at the Elysee Palace on Tuesday that the top priority was blocking the RN from power.

That would involve supporting members of the far-left France Unbowed party (LFI) if necessary, Macron said, despite some opposition from members of his own party.

LFI party member Francois Ruffin also said on Tuesday that there was unity in “one objective … to deny an absolute majority to the National Rally.”