Greece was to submit a detailed bailout request to its EU partners in the eurozone Thursday in a last-ditch effort to save its collapsing economy and its membership in the European single currency.

Prime Minister Alexis Tsipras vowed on Wednesday that his country's new plan asking for billions in euros would contain "concrete proposals, credible reforms, for a fair and viable solution".

But other eurozone nations, led by Germany, are sceptical about Greece meeting austerity conditions attached to the loans, especially after Greeks in a referendum last weekend backed Tsipras's past rejection of tough terms on its last bailout.

"This is really and truly the final wake-up call for Greece and for us, our last chance," said EU President Donald Tusk on Wednesday.

Failure "may lead to the bankruptcy of Greece" and geopolitical problems for Europe, he said.

Leaders of the 28-nation European Union, including the 19 states that share the euro, are to hold a summit on Sunday billed as the "final deadline" for a deal.

While Europe has no provision under its treaties to force a country out of what is meant to be an "irreversible" monetary union, some legal advisers say it could be made to happen by kicking an errant state out of the European Union.

A demonstration of Greeks calling for their country to remain in Europe was to take place in central Athens late Thursday.


Brink of collapse


Greece, which has until midnight Brussels time (2200 GMT) to file its reform proposals for what would be its third bailout in five years, is teetering on the precipice of financial collapse.

Banks are closed and ATMs, whose daily withdrawal limit is capped at 60 euros ($67) per card holder, are expected to start to run dry any day now. The capital controls also ban overseas money transfers, isolating Greece and its population of 11 million from foreign suppliers of everything from food to medicine.

Authorities have extended the closure of the banks and the Athens stock market to next Monday.

The number of last-minute tourist bookings to Greece -- usually a European summer hotspot for its many sunbleached islands -- has plunged 30 percent over the past two weeks because of the uncertainty.

International markets, though, appear relatively sanguine about the possibility of contagion from a "Grexit", or Greek exit from the eurozone, despite an initial dip after the referendum.

In Asian trade on Thursday, the euro ticked up to $1.1095 against $1.1074 in New York the previous day.

US President Barack Obama has urged Europe to keep Greece in the eurozone.

US Treasury Secretary Jacob Lew said that "Greece's debt is not sustainable" and creditors needed to look at restructuring it -- something Germany in particular has said it will not do until Athens shows a commitment to reforms.

France and Italy have expressed a strong desire to see Greece remain in the euro club, even if their line with Athens had become firmer.

French Finance Minister Michel Sapin told French radio on Thursday that "we are starting to see the beginnings of chaos in Greece".

He asked, "Is it in European citizens' interests... to have a country crumble where its authority dissipates?" and pointed out that Greece is a country of transit for migrants trying to get to Europe.

Difficult' situation


A team of French experts was helping Greece prepare its crucial bailout reform plan for submission, Greek media reported.

Greece's new finance minister, Euclid Tsakalotos, disappointed his eurozone counterparts when he turned up to a meeting Tuesday without any concrete plans for ending the standoff.

On Wednesday, Tsakalotos asked the eurozone's crisis fund, the European Stability Mechanism, to give a three-year loan for an unspecified amount to Greece.

He promised that, in exchange, Greece would "immediately implement a set of measures as early as the beginning of next week" dealing with pensions and tax reform -- the two main areas of disagreement with creditors.

There was no immediate reply from the ESM made public.

The European Central Bank on Wednesday left untouched its cap on a 89-billion-euro ($99-billion) lifeline it had previously extended to Greece's banks.

Throughout the turmoil of the past couple of weeks, the ECB has appeared to want to take a neutral path that would neither help Greece out of its hole nor push it in deeper.

But its chief, Mario Draghi, who in 2012 famously defended the euro by saying the ECB would do "whatever it takes" to save the currency, had doubts about Greece staying in the eurozone.

On Wednesday as he arrived in Rome on a flight from Brussels, he was asked by Italian journalists if Greece's situation would be successfully resolved.

"I don't know. This time, it's really difficult," Draghi said, according to the newspaper Il Sore 24 Ore.