By Jonathan Davies
The new Greek government made "completely unrealistic promises" that it cannot fulfil, according to the former president of the European Commission.
The Syriza party won the election in January largely based on its anti-austerity policies, pledging to not pay back its €240bn bailout debt.
But Jose Manuel Barroso, who left the European Commission in October, told the BBC that Greece's demand were "completely unacceptable to other countries".
Mr Barroso said: "We should remember that there are poorer countries that are lending money to Greece, so to propose a cut to their debt would be certain to receive a no from their partners."
The former European Commission president said that Greece needs to take responsibility for its financial problems and implement the structural reforms agreed by the government, the European Central Bank, the European Union and International Monetary Fund (IMF).
He said: "It was not Germany or any other member of the EU that created the problems in Greece, the problems in Greece are structural: low productivity and previous governments."
Greece has consistently been on the verge of running out of money for months, but the international creditors are adamant that Greece must implement economic reform as some form of insurance policy to show that it will be able to better manage its finances.
Mr Barroso pointed to the examples of Ireland, Portugal and Spain - countries that have come back from bailouts. He said: "There is nothing regarding Greece that prevents it being successful, but... bad politics have created a lot of problems for Greece."