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."