French President Emmanuel Macron appointed Michel Barnier, the European Union's former Brexit negotiator, as his new prime minister on Thursday, in a bid to put an end to political paralysis following an inconclusive snap election.
The discreet, conservative politician will quickly face a baptism of fire as time is running out to prepare France's 2025 budget, which could trigger a vote of no confidence if parties in the bitterly divided parliament are not satisfied.
The leftwing alliance that won June's election accused Macron of ignoring the result by picking a conservative. It called for demonstrations against Barnier's selection but does not have enough seats to block the choice on its own.
The far-right National Rally (RN), parliament's biggest single party, indicated it would not block Barnier for now, but could do so later if a range of demands were not met.
At 73, Barnier is the oldest prime minister in France's modern political history, taking over from Gabriel Attal, who was the youngest.
"The election has been stolen," hard-left leader Jean-Luc Melenchon said. Another hard-left lawmaker, Mathilde Panot, called it an "unacceptable democratic coup".
Macron had ruled out asking the left to form a government after other parties said they would immediately vote it down.
RN leader Jordan Bardella said the party acknowledged Macron's choice and would judge Barnier's "general policy speech, his budgetary decisions and his actions on their own merit".
"We will plead for the major emergencies of the French -- the cost of living, security, immigration - to finally be addressed, and we reserve all political means of action if this is not the case in the coming weeks."
Barnier is a staunch pro-European and a moderate career politician, but he toughened his discourse considerably during his failed 2021 bid to get his conservative party's ticket for the presidential election, saying immigration was out of control.
Barnier first became a lawmaker aged 27, and later held roles in several French governments, including foreign minister and agriculture minister. He is best known abroad for having led the EU's talks with Britain over its exit from the bloc from 2016-2021.
Macron had considered a string of potential prime ministers in recent weeks, none of whom mustered enough support to guarantee a stable government, which was his main goal.
French bank shares edged up after Barnier was appointed. Government borrowing costs fell slightly after the announcement, while the euro nudged higher, in positive signs from financial markets.
Barnier's political views are overall close to Macron's, and it was crucial for the French president that his new prime minister not try to undo reforms pushed through over the past years, in particular pension changes that angered the left.
It remains unclear if Barnier will fully try to implement Macron's political agenda or bring in new proposals. He will need in any case to negotiate with other parties to get legislation adopted in parliament.
As Macron's hunt for a prime minister dragged on, public finances deteriorated and outgoing Finance Minister Bruno Le Maire has said that tens of billions of euros in budget cuts are needed to plug the hole.
Macron's gamble to call the snap parliamentary election in June backfired, with his centrist coalition losing dozens of seats and no party winning an absolute majority. Voters did, however, rally to deny the RN a victory.
RN lawmaker Laurent Jacobelli said a condition for not voting Barnier down would be that parliament be dissolved as soon as possible - which would be early July next year. Barnier should also signal support for a change to proportional representation to replace France's system of two-round voting for single constituencies, he said.
He made clear the RN was not particularly enthusiastic about Barnier.