Eurozone finance ministers meeting in Brussels have said that more work needs to be done before they can agree to give Greece an extra €130bn on bailout funds.
After weeks of talks, Greek politicans earlier agreed a programme of austerity measures, which involves over 15,000 public sector layoffs and a lowering of the minimum wage.
Tonight, the Eurogroup chairman, Jean Claude Junker, said the Greek parliament will also have to pass the full reform package on Sunday and party leaders have to make clear that they will back the measures after elections, which are due in April.
Mr Junker also said an extra 325 million euro in savings for 2012 will be needed.
Minister for Finance Michael Noonan said that while significant progress had been made in Athens, it seemed to him that it was too early to say a deal had actually been concluded.
Germany's Finance Minister Wolfgang Schaeuble also said that Athens did not yet appear to have fulfilled all the conditions for a bailout.
Greek Finance Minister Evangelos Venizelos had earlier appeared optimistic about reaction to the deal.
"I leave for Brussels with hope that the Eurogroup will take a positive decision concerning the new aid plan," Mr Venizelos said prior to his departure.
Greek leaders reach agreement on bailout
Greece's coalition leaders announced that they had reached a "general agreement" on additional austerity measures demanded by EU-IMF creditors in return for a debt bailout.
"There is a general agreement on the contents of the new programme," the government said in a statement, referring to a eurozone bailout worth €130bn that officials have discussed since October.
Marathon talks between the socialist, conservative and far-right parties backing the government of Prime Minister Lucas Papademos had concluded early this morning short of a full deal, with €625m in budget cuts missing.
The party leaders had initially balked at ordering cuts to complementary pensions in a biting recession to make up around half of that shortage.
"Consultations with the troika on the issue left open for further discussions were successfully concluded this morning," the government said.
"The political leaders agreed with the result of these consultations," it added without giving further details.
The new measures have not been too well received in Greece and Deputy Labour Minister Yannis Koutsoukos has resigned.
Mr Koutsoukos, a member of the Socialist PASOK party, said in a letter to the prime minister that he was resigning because the measures were not only "tough", but also "painful for working people".
European Central Bank chief Mario Draghi told reporters in Frankfurt that he had received a phone call from Greek Prime Minister Lucas Papademos just minutes earlier.
Mr Draghi said: "He told me that agreement has been reached and has been endorsed by major parties."
