Greece's independent statistics agency has said the country's economy grew by 1.3% on the year in the previous quarter.
That figure failed to meet ambitious expectations from the government and European Union.
Without a revision, the July-September growth figure announced on Monday suggests that Greece could miss its target of annual growth of 1.6%.
The data was released as eurozone finance ministers in Brussels discussed Greece's bailout programme and a technical agreement reached over the weekend between Athens and creditors on the terms of future disbursements.
Greece is set to exit the rescue programme in August but continue austerity measures for at least another two years.