As a result, analysts warned that Greece could delay no longer and had no room for maneuver.
"Another 'kick of the can down the road' is not possible," Athanios Vamvakidis, head of European G10 foreign exchange strategy at Bank of America Merrill Lynch, said in a note Wednesday.
"Greece would be forced to exit the euro without reforms," he added, saying it was the "end of the road" for Greece and its euro zone neighbors.
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Greece's new left-wing government has struggled to impress its international creditors since it came to power in January. The country has received 240 billion euros ($262 billion) in aid as part of two financial bailouts since 2010, but it still has the highest unemployment rate in Europe, at 25.7 percent, and the highest debt pile, which is around 175 percent of gross domestic product (GDP).
In February, Greece was given a four-month extension to its bailout program, but it has yet to convince the bodies overseeing its bailout – comprising the European Central Bank, European Commission and International Monetary Fund (IMF) -- that it is serious about reforms.
Vamvakidis outlined three possible scenarios for Greece, with the best being a commitment to reforms, leading to positive growth surprises.
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The "bad" and "ugly" alternatives were more worrying, he said. The former would see Greece doing just enough to stay in euro zone, whereas the latter scenario -- in which there is no deal between Greece and its creditors -- "leads to a bank run, capital controls, and eventually Euro exit."
"It could also be the case that triggering the bad, or even the ugly scenario would force a political consensus in Greece to move to the good scenario, but the situation will likely have deteriorated substantially in the meantime," he said.