WASHINGTON (AFP) - Rating firm Fitch on Friday lowered Greece's credit outlook to negative from stable, citing rising political uncertainty, but kept the country's credit rating unchanged at 'B', indicating highly speculative.

"The current period of political uncertainty has increased the risks to Greece's creditworthiness as official financing, and any potential reopening of market access, could be delayed for some months. Early elections to be held on Jan 25 have made the direction of Greek policymaking more uncertain," Fitch said in a statement.