After being forced to abandon plans for a referendum on the EU bailout fund, George Papandreou will learn if his government has the backing of the Greek parliament.
In an drama which has become almost impossible to predict, the future of Mr Papandreou and his government will be decided by a late-night vote in the Greek parliament.
Intense European pressure forced debt-stricken Greece to seek political consensus on a new bailout plan instead of holding a referendum.
It came as EU leaders raised the prospect of a Greek exit from the euro to preserve the single currency.
Late on Thursday, Greece’s opposition leader made demands for the beleaguered prime minister to resign, before leading a walkout from parliament.
The crisis facing Greece overwhelmed the G20 meeting in Cannes as Mr Papandreou was forced to backtrack on his pledge to hold a referendum on the EU bailout.
The Greek prime minister, whose father and grandfather were prime ministers, hinted he was ready to quit for the sake of national unity, telling parliament he was not wedded to his job.