European leaders have expressed cautious optimism after Greece offered economic reforms that creditors consider potentially acceptable, giving the country a couple of days to try to secure a bailout deal.
Alexis Tsipras, Greek prime minister, presented the proposal on Monday that was expected to be reviewed by Thursday when the EU leaders will gather for a two-day summit.
Donald Tusk, EU president, said the proposals were the "first real proposals for many weeks" from the Greek government which has resisted calls by creditors for further cuts to pensions and changes to taxes.
But Tusk warned of the consequences of failure, with Greece at risk of defaulting on a $1.7bn debt payment to the International Monetary Fund on June 30 if it fails to get a deal to extend its international bailout by the same day.
"The most important thing is that the leaders take full responsibility for the political process to avoid the worst case scenario, which means uncontrollable, chaotic 'Grexident'," Tusk said, using the term for a failure to prevent Greece leaving the euro.
Jeroen Dijsselbloem, head of the eurogroup of eurozone finance ministers, said that Monday's proposal was "a welcome step and a step in a positive direction, so I think it is also an opportunity to get that deal later this week".
Dijsselbloem said, however, that more work was needed and the eurogroup would probably have to meet again later this week, before another summit of all 28 EU leaders on Thursday.
The Greek proposal sent to Brussels overnight was a last-ditch bid to unlock the final 7.2 billion euro tranche of its international bailout, which creditors have refused to release unless Greece agrees to more austerity measures.
Giorgos Stathakis, Greek economy minister, told the BBC on Monday that the proposal adhered to the Greek government's determination not to cut pensions further.
"There will be new taxation on business and the wealthier part of society and we will save pensions and wages," he said.
Greece needs the money to pay the IMF, one of its three bailout monitors along with the European Commission and European Central Bank.