The International Monetary Fund says Greece needs debt relief and 50 billion euros ($56 billion) in new financing from October through 2018.
The IMF said Thursday that Greece's finances have deteriorated because Athens has been slow about enacting economic reforms. Last year, the IMF predicted Greece's debt would fall from 175 percent of economic output in 2013 to 128 percent in 2020. Now it sees Greece's debts at 150 percent in 2020.
The IMF says creditors must offer Greece discounted interest rates and a longer repayment period.
The analysis was made before Greece defaulted on IMF loans Tuesday and closed its banks Monday. The outlook is worse now.
Greeks vote Sunday on whether to accept demands that creditors were proposing to resolve a debt standoff.