The head of Tunisia's anti-Islamist Nidaa Tounes party, Beji Caid Essebsi, leads the country's presidential election with 39.46 percent of votes, six percentage points ahead of incumbent Moncef Marzouki, results showed Tuesday.
Because there was no outright winner, a second round of voting will now be held, with the date depending on any appeals, the head of the ISIE elections body Chafik Sarsar told reporters.
Marzouki secured 33.43 percent of votes cast in an election European Union observers on Tuesday called "pluralist and transparent".
Leftwing figurehead Hamma Hammami came third with 7.82 percent, followed by London-based Islamist entrepreneur Hechmi Hamdi (5.75 percent) and wealthy businessman and football club president Slim Riahi (5.55 percent).
Sunday's election was the first time Tunisians had voted freely for their head of state since independence from France in 1956.
The North African nation that sparked the Arab Spring had known just two presidents -- "father of independence" Habib Bourguiba and Zine El Abidine Ben Ali, who was forced to flee on January 14, 2011 by a popular uprising.
Marzouki was elected president at the end of 2011 by the National Constituent Assembly under a coalition deal with the then ruling Islamist Ennahda party, which came second in a parliamentary election last month behind Nidaa Tounes.