Last Updated Jul 8, 2015 4:15 AM EDT
BRUSSELS -- Greece was scrambling Wednesday to develop a detailed proposal to move away from the brink of financial collapse.
Prime Minister Alexis Tsipras attended a meeting in Brussels on Tuesday with eurozone finance leaders and was told his country had to develop a proposal by Thursday. Creditors will then assess the plan to prepare for another meeting of eurogroup finance ministers and ultimately Sunday's summit of the full EU.
Officials expressed frustration and even anger that Tsipras came to Tuesday's meeting without a detailed plan for acquiring a new bailout.
"The process will be swift, it will be speedy. It will begin in the next few hours with the aim of concluding (by) the end of the week at the latest," Tsipras said, making it clear he got the message that there wasn't a moment to waste.
The Greek government is asking for a three-year loan from Europe's bailout fund and is vowing to implement tax and pension reforms starting on Monday. Athens said in a letter that it plans to "set out in detail" the government's reform agenda no later than Thursday.
Meanwhile, European Commission President Jean-Claude Juncker said authorities were prepared for all eventualities -- including a scenario in which the debt-laden country leaves the euro single currency or the European Union itself.
"Our inability to find agreement may lead to the bankruptcy of Greece and the insolvency of its banking system. And for sure, it will be most painful for the Greek people. I have no doubt that this will affect all of Europe, also in the geo-political sense," warned European Council President Donald Tusk on Tuesday.
"The stark reality is that we only have five days left to find the ultimate agreement. Until now I have avoided talking about deadlines, but tonight I have to say it loud and clear that the final deadline ends this week," Tusk added. "All of us are responsible for the crisis and all of us have a responsibility to resolve it."
Tsipras, who was elected on an anti-austerity platform, stunned observers by calling for a referendum on Europe's last bailout proposal, which was already off the table by the time of Sunday's vote. CBS MoneyWatch's Jonathan Berr reported that observers were further surprised when Greeks voted "no" by a 61 percent majority.
"The referendum has made the political situation in creditor countries much more difficult," said Christian Odendahl, chief economist at Centre for European Reform, a London-based think tank, in an interview with CBS MoneyWatch.
Berr said Tsipras has benefited from a feeling among Greek citizens that after suffering through years of austerity, they don't have anything to lose. But his support could crumble, particularly if he's unable to secure a deal before July 20, when Greece's 3.5 billion euro ($3.9 billion) payment is due to the European Central Bank.
If that bill goes unpaid, the ECB will cut off the aid it has been giving Greek banks to keep them afloat. Greece skipped a $1.7 billion payment due to the IMF last week, which cuts off further help from that organization. The country's European bailout package has also expired.