A detailed list of concrete reforms from Greece had yet to be submitted to the country's international creditors Monday, prompting analysts to warn that Greece risks are rising – again.
The country's leftwing government outlined some reforms on Friday, but officials from the bodies overseeing its bailout – the International Monetary Fund (IMF), European Commission and European Central Bank (ECB) – were not convinced by its latest attempt to get a final – and desperately needed – tranche of aid.
One euro zone official told Reuters that the list resembled more of a "collection of ideas," than something to be presented to the Eurogroup of finance ministers, while another said a more technical list could be received Monday. The measures have to be approved by the euro zone ministers before more financial aid is released to Greece.
Time is tight for the country, which is expected to run out of money by April 20, according to a Reuters report. It has loan repayments to make to the IMF and a large wages and pension bill coming up which will put further pressure on its depleted finances.
'Crunch time'
Against a backdrop of seemingly never-ending wrangling over Greece, investors are becoming increasingly nervous. Since a deal was struck to extend Greece's current bailout program by four months in February, the Athens Stock Exchange has declined almost 24 percent.
Economists at UBS warned that Greek risks would rise in April, as negotiations between the country and its international partners on the future of its bailout program show a lack of concrete progress.
"Although the government has pledged to present a reform list early (this) week, we expect negotiations to remain protracted, and given substantial debt service in the coming weeks, we think market sentiment might turn a lot more nervous again in April," UBS economists and strategists led by Reinhard Cluse said in a note Friday.
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They warned that this could trigger further deposit outflows from the Greek banking sector.
But although April looks difficult, UBS said the "ultimate crunch time" would come in the middle of the year, ahead of large debt repayments due in July and August, "which appear daunting in the absence of a comprehensive deal between Greece and its creditors."
"Our base-case scenario remains that a compromise will eventually be found, but the path towards this outcome is likely to be bumpy and the risk of failure has to be taken seriously, in our view," they added.
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Despite analysts' concerns, Greece's government remains optimistic.
Economy Minister George Stathakis has said that he expects an agreement to be reached with creditors on economic reforms and funding for the Greek government.
Speaking to Greek television network, Antenna TV, on Friday, he said: "I think at the beginning of next week we will have a deal, both over the reform package proposed by the Greek government, and over the flow of funding."
This confidence could be misplaced, however, according to Jack Allen of Capital Economics. He said in a note Monday that "given the gulf between the two sides, it is unclear how long-lasting any agreement, if indeed one is reached, will be."
'This time, baby?'
As fatigue over Greece increases, many analysts are now asking when -- not if – the country will leave the euro zone.
Simon Derrick, chief currency strategist at BNY Mellon, told CNBC that the only question one can ask about Greece and its reform pledges is: "This time, baby?"
"The only other question you can possibly ask is whether, if we finally did get a Greek exit from the euro zone, would there be a collective shrug of the shoulders and everybody would say: 'Finally, we can now get on with things,'" Derrick said on CNBC Europe's "Squawk Box."
"Having spent some time in Europe over the last couple of weeks, I think collectively that is the opinion. You raise the topic of Greece and everyone says: 'Yeah, fine. Look, we know they should be out, and if they were, so what?'"
He added that we'd moved from a point where the idea of a Greek exit from the euro zone -- known as a "Grexit" – was anathema, to a point where people are ready to let Greece go. "They should go, that's the simple point," Derrick said.
- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt. Follow us on Twitter: @CNBCWorld