As Greece's creditors line up to oppose the country's demand for a debt restructuring, Prime Minister Alexis Tsipras's refusal to accept more bailout loans may result in a cash crunch as early as next month, two people familiar with the country's financial position said.

Unless the 15 billion-euro (US$17 billion) limit on short-term borrowing set by Greece's troika of official creditors is raised, the government may run out of cash on Feb. 25, said one of the people, who asked not to be named because the figures are confidential. Three weeks ago, international officials reckoned Greece could hang on until mid-year.

With Greeks yanking their cash from banks and withholding tax payments, Tsipras would only be able to survive for a few more weeks by tapping social-security funds and withholding payments to vendors, the person said. By the end of March he may face existential choices: accepting a lifeline with conditions he has consistently rejected or abandoning the euro.