"In a government, there cannot be any personal initiatives and even less presidential ones," Hollande said in a TV interview to mark the Bastille Day national holiday.
"Respecting these rules means staying in the government. Not respecting them means leaving."
READ MORE: Hoax or cunning plan: Macron for President?
Political observers and even his Socialist Party colleagues are asking how long Macron can stay in the cabinet after he strongly hinted at a presidential bid in a speech this week.
The 38-year-old former investment banker stopped just short of throwing his hat into the ring for next May's election.
But his pledge on Tuesday to lead his En marche! (On the move) political movement "to 2017 and to victory" left little doubt about his intentions.
Hollande himself has said he will decide by the end of the year whether to stand for re-election as the Socialist candidate despite opinion polls currently showing that he would be eliminated in the first round of voting.