If Greece did default on its debts and capital controls were issued, a Grexit would not necessarily be inevitable, the economists said. But they added that this could lead to a drawn-out process – a Greek limbo that could, if the gridlock persisted, lead to a Grexit.
"Grexit in the next few months is not inconceivable, and it is certainly more likely if we consider Grimbo durations of a year or more," Buiter and his colleagues remarked.
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The warning comes against a backdrop of fraught, drawn-out negotiations over Greece's financial future. On Friday, the Eurogroup of euro zone finance ministers is meeting in Latvia to discuss Greek reforms in return for aid.
Neither the ministers involved in the discussions nor analysts are confident any agreement will be reached, however, raising the prospect that the issue will be kicked further down the road while Greece's funds run low and bankruptcy approaches.