|Al Jazeera's Jonah Hull reports from Athens, Greece's capital, on the growing political standoff
George Papandreou, the Greek prime minister, is facing a crucial confidence vote after being forced to back down from a proposed referendum on an EU bailout plan for the debt-crippled country.
Even if his Socialist government survives Friday's parliamentary vote, Papandreou's days as Greek leader looked numbered after Antonis Samaras, a Greek opposition leader, called on the prime minister to resign and repeated a call for early elections.
Samaras made the demand on Thursday during a parliamentary meeting to vote on whether to accept the EU package that contains deeply unpopular spending cuts.
"Even if [Papandreou] wins the vote, he is a mortally wounded prime minister who does not even command the respect of his inner circle"
- Yanis Varoufakis, professor
Papandreou said that calling early elections would be "catastrophic" and said Greece must implement the EU bailout plan.
The developments came after Papandreou told his cabinet earlier on Thursday that he would drop plans for a nationwide referendum on the plan if the oppositon joined him in a coalition.
Much of Greece and many European leaders reacted with horror after Papandreou abruptly announced on Monday that he would put the $180bn rescue plan, agreed at a eurozone summit last week, to the Greek people.
Through waves of austerity policies demanded by the nation's international lenders, Papandreou has carried the parliamentary group of his PASOK party with him, despite much criticism within the ranks.
But a steady number of defections has reduced his majority to the point that one or two waverers could inflict a defeat in the confidence vote, expected late on Friday (22:00 GMT).
PASOK has 152 deputies in the 300-member parliament. But legislator Eva Kaili said that while she would stay in the party, she would refuse to support the government in the confidence vote, meaning Papandreou could count at most on the support of 151 deputies.
Only one more defection would strip the government of its majority and probably trigger early elections.
'Lacks political legitimacy'
Yanis Varoufakis, an economics professor at the University of Athens, told Al Jazeera that "it is not inconceivable that Papandreou is going to win the vote of confidence".
"Because his members of parliament have to decide between sacrificing their seats - because this is what will happen if the government falls, they will have to face the electorate - and vote in the manner which will allow them to walk around the streets of Athens in their own towns and villages with their heads held high," he said.
"This government lacks political legitimacy, but then again politicians have been known to vote in a manner which promotes self-interest.
"But even if he wins the vote, he is a mortally wounded prime minister who does not even command the respect of his inner circle."
Costas Panagopoulos, the head of ALCO pollsters, said: "The prime minister's position is very difficult, since he chose not to respond to the opposition's proposal for a transitional coalition government.
"Therefore I believe that it is unlikely that he will win the vote."
'Agreed to step down'
Greeks have fought very fiercely against policies which have brought spending cuts, tax rises and job losses, pushing the nation into three years of recession.
Demonstrators have staged a series of strikes and protests, some of which turned violent.
This made a "no" vote in any referendum highly probable, even though this would cut off Greece's last international financial lifeline and risk spreading its debt crisis to much bigger eurozone economies, such as Italy and Spain.
Papandreou has called on his PASOK party to rally behind him in the confidence vote.
But his public bravado appeared to mask an acceptance that his term may come to an end soon.
In a major blow, Evangelos Venizelos, Greece's finance minister, broke ranks on Thursday with Papandreou over the referendum proposal, saying Greece's status in the eurozone should not be put to a popular vote.
German Chancellor Angela Merkel and French President Nicolas Sarkozy summoned Papandreou and Venizelos to Cannes on Wednesday, where they made clear Greece would receive no EU aid if the nation failed to stick to the deal.