"The renegotiation that I want must be possible," Francois Hollande told a prime-time French television interview 10 days before a vote run-off pitting him against incumbent Nicolas Sarkozy that he is tipped to win.
"It's not Germany that's going to decide for all of Europe," Hollande said, after German Chancellor Angela Merkel repeated her position that the pact was not up for renegotiation.
"Lots of countries today are waiting for France's decision, because we aren't any old country in Europe, we're a leading country in Europe and what the French people are going to do will considerably change the order."
The fiscal pact, clinched after marathon talks by EU leaders in March, is a German-inspired accord that aims to combat the crisis via austerity which was signed by all 27 EU countries except Britain and the Czech Republic.
One of the pillars of Hollande's campaign has been calling for the pact to be renegotiated to include measures for growth and he has vowed to veto it if he considers such moves insufficient.
Hollande's plan received a surprise boost on Wednesday when European Central Bank chief Mario Draghi called for a "growth compact" to complement the eurozone's fiscal compact.
But Hollande's opponent Sarkozy dismissed this later in the same broadcast, insisting that his stricter budget cutting strategy was the only way to escape the downturn.
"I can think for myself, I don't need to get my orders from Mr. Draghi," he said. "To take back control of our own destiny, we have to repay our debts. We can't live beyond our means," he said.
France returns to the polls on May 6 for Hollande and Sarkozy's run-off.