Socialist Francois Hollande, who won the first round of France's presidential poll, was challenged by President Nicolas Sarkozy, to hold three public debates with him before the second round of the vote.
"I propose that three debates be organised. The French have the right to truth and clarity," Sarkozy said on Sunday, challenging Hollande.
Hollande set up a run-off with Sarkozy, after he won the first round of France's presidential poll.
Hollande got about 28 percent of votes Sunday, according to projections based on partial results, against about 26 percent for centre-right incumbent Sarkozy.
Hollande in his speech at his headquarters in Tulle, south west France, said "Tonight, I become by the French vote the candidate of all the forces who want to close a page and open another. Thanks to you, tonight, change is now running, and nothing, I say nothing, will stop it,"
"On May 6, I want a great victory worth of France of its history and its future," he told his supporters.
Portraying himself as the best candidate to cruise to the Elysee Palace after Sunday's results, Hollande urged a large gathering which 'should be as wide as possible' to be there during the decisive round scheduled on May 6.
The two leading candidates will meet in a second round May 6.
Presidential frontrunners Sarkozy and Hollande are set to resume their duel April 27 with a series of campaign rallies. A face-to-face television debate is scheduled for May 2.