Prime Minister Costas Karamanlis has confirmed that Greece will hold a snap parliamentary election on 16 September.
The Greek prime minister had until March to hold elections
Speaking on TV, Mr Karamanlis said he had formally requested the dissolution of parliament and new polls in a letter handed to President Karolos Papoulias.
Mr Karamanlis, who called the poll six months before his government's term ends, is seeking a mandate for reform.
Opinion polls suggest his conservative New Democracy party is only just ahead of the opposition Socialists.
A series of scandals and an unpopular reform programme are among the issues which have dented the government's popularity since its win in 2004.
In that election, New Democracy won 165 of the 300 seats in the Greek parliament, ending 11 years of uninterrupted government by the Socialist Party (Pasok).