The center-right candidate has repeatedly denied all accusations and pressed on with his election campaign despite a dip in popularity. His party has been pressed to look for alternatives for his candidacy, with his former primaries rivals among those rumored to be up for replacing him.
Fillon has called the media storm a "political assassination." He is expected to face investigators on March 15, after which formal charges may be made.
"Today I am unable to attain the necessary unity over one project, so I confirm I will not be a candidate in the presidential election," Juppe said, speaking in the city of Bordeaux.
On the same day, Fillon vowed to the presidential race, stressing that "no one has the power" to force him out.
The first round of the French presidential election is scheduled for April 23, with the run-off set for May 7.
