France edges ever closer to far right
Juppe, 71, was the most likely candidate to step in for Fillon and try to unite their deeply divided Republicans party only seven weeks from the start of the two-stage election.
Polls suggest Juppe would be more popular with voters, but the centrist is considered too soft on immigration and other social issues for many of Fillon's supporters and the right flank of the party.
"I confirm for a final time that I will not be a candidate to be president of the republic," Juppe said in a downbeat statement that criticised Fillon and the "confused" conditions for the election.
His decision removes a major rival for Fillon, whose bid for the presidency remains on track despite mounting criticism within the party and falling poll numbers.
The conservative 63-year-old was once a clear favourite to be France's next leader but his campaign is mired in accusations that he used public funds to pay his wife hundreds of thousands of euros for fake parliamentary jobs.
"No one today can prevent me being a candidate," Fillon said on Sunday, adding that the accusations against him were "aimed at stopping me being a candidate".
The chaos in Fillon's camp has made an already unpredictable election even harder to call. It appears to have benefited centrist pro-business candidate Emmanuel Macron in particular, as well as far-right leader Marine le Pen, who are shown by polls as the top two candidates in the first round on April 23.
Polls suggest that Macron, 39, would beat Le Pen in the decisive second round, but after Donald Trump's rise in the US and Britain's vote to leave the EU, analysts caution against bold predictions.
Ahead of a crisis meeting of leaders from the Republicans party yesterday, former president Nicolas Sarkozy piled pressure on Fillon to meet Juppe and find a way out of the crisis.
The current French leader, Francois Hollande, also warned that the threat of a Le Pen presidency was real but that he would fight to prevent it happening.
"The far right has not been so high (in the polls) for more than 30 years but France will not give in," the president said.
France "is aware that the vote on April 23 and May 7 will determine not only the fate of our country but also the future of the European project itself", he added.
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