The decision to support Francois Fillon's candidacy was taken at an emergency meeting after former prime minister Alain Juppe ruled out replacing him.
An emergency meeting of the French conservative party's leadership unanimously backed Francois Fillon as candidate for the presidential election, a senior party official said on Monday.
The leader of the conservative The Republicans' party, Bernard Accoyer, confirmed the deal, saying the party had reunited and was re-launching Fillon's campaign.
Former French prime minister Alain Juppe had earlier on Monday ruled out replacing scandal-hit Fillon in the coming presidential election but offered no alternative candidates.
TRT World's Simon McGregor-Wood has more details.
'Only legitimate candidate'
Earlier, Fillon urged his conservative party to rally around him, saying he was the only legitimate candidate, despite calls by many in his camp for him to pull out of the French presidential race over allegations of misuse of public funds.
"It is time for everybody to get their act together and come back to their senses," he told senior party members gathered to discuss the crisis, according to a text.
Fillon, who overwhelmingly won primaries organised by The Republicans party and their allies in November, added, "I call on all the women and men of goodwill to rally, respect the message our voters sent during the primaries and unite behind my candidacy, which is the only legitimate one."