The International Monetary Fund (IMF) said in its report on Thursday that Greece requires €50 billion and easier terms on existing debt from October 2015 to end 2018 to maintain its finances sustainable, including at least €36 billion from Eurozone.
The IMF expects that Athens needs about €29 billion over the next 12 months from October 2015.
The lender downgraded Greece's economic growth forecast for this year to zero from April's estimate of 2.5%
The IMF said that state deposits in the Greek banking system dropped to less than €1 billion at the end of May.
The IMF noted that the report didn't reflect developments that happened since it was prepared, including bank closures, capital controls and IMF arrears.
"Greece faces a significantly larger financing need going forward than we thought last year," a senior IMF official said