PARIS—French President Emmanuel Macron has lost his majority in the National Assembly, as voters in France’s parliamentary elections delivered a blow to his pro-business agenda and positioned leaders on the far-left and far-right to wield unprecedented influence.

Results showed that Macron’s party, Renaissance, and its allies won 245 seats in the 577-seat National Assembly. That gives him the most seats in France’s lower house, but not enough to retain the majority that allowed the French leader to steamroll the opposition during his first term.