Preliminary results show Mr Erdogan's Justice and Development Party (AKP) won about 50 percent of seats in June 12's vote.

But the party failed to secure the two-thirds majority needed to make unilateral changes to the constitution.

Mr Erdogan had widely been expected to win despite criticism from some of his authoritarian style of leadership.

With 99 percent of ballots counted the AKP had 50 percent of the vote, which local media said translated to 326 seats in parliament.

That is short of the 330-seat "super majority", which would have enabled the party to make constitutional changes without putting it to a public referendum.

The party won 341 seats in 2007. Accepting his victory in Ankara, Mr Erdogan said his party "will be humble".