Greek Prime Minister George Papandreou is ignoring a chorus of calls for his resignation, despite a day of political turmoil that climaxed when opposition politicians staged a dramatic walkout during a crucial parliamentary confidence debate.

Greece's Opposition leader Antonis Samaras led the walkout Thursday, after the prime minister flip-flopped on a planned referendum that has jeopardized an urgent European Union bailout plan for the nation's disastrous economy.

The spectre of a referendum on the bailout rattled global markets this week, and ramped up the political pressure to find a solution to the mounting debt crisis. Papandreou has since backed off the referendum plan, but his many critics have only strengthened their attacks.

"Mr. Papandreou pretends that he didn't understand what I told him. I called on him to resign," Samaras said in Parliament. "He set fires everywhere, and returned as if nothing happened. A return to normality means elections -- within the next six weeks if possible."

It was the latest development after a day of political turmoil in Athens, in which Papandreou's government hung by a thread. And there is more turbulence ahead, with the prime minister due to face a confidence vote at midnight on Friday.

Papandreou has even been pressured by some of his own cabinet ministers to resign and let a coalition government approve the bailout plan put forward by the EU.

Facing mounting political pressure at home, he suggested that he might leave his post before the country's next vote is held.

"I don't care about being re-elected. I am interested in saving the country," he said, adding that he was open to the possibility of a transitional government securing the EU debt deal before holding an election.

"Let everything be discussed -- the makeup of the government and anything else. ... I am not glued to my seat."

The debt agreement, which was reached last week after months of negotiating, would have given Greece 130 billion euros while cancelling 50 per cent of its debt. In exchange, Greece would have had to accept more austerity measures.

But that deal was suddenly put in jeopardy Monday when Papandreou announced he would leave it to the Greek people to decide whether to accept the deal in a December referendum. Reports suggested about 60 per cent of Greeks would have voted against the deal, which likely would have plunged Greece into bankruptcy and led to its ouster from the EU.

EU leaders appeared caught completely off guard by the move.

Samaras said that the prime minister "nearly destroyed Europe and the euro ... and all this to claim that he wanted to blackmail us into accepting the loan arrangement, even though I had said it from the beginning that it was unavoidable."

Greece has been in a state of uproar for several months as the government has brought in rounds of austerity cuts. Many daily strikes and protests have turned into riots.

Despite the ongoing calls for Papandreou to step aside, government spokesman Ilias Mossialos said on Thursday that "we are ready for a serious discussion" on the conservative opposition's proposal.

Papandreou also outlined his plans during an impassioned emergency cabinet meeting, CTV London Bureau Chief Tom Kennedy reported.

"He described all Greeks as soldiers in an army that must fight for the salvation of the country, so you can see the rhetoric he's using," Kennedy reported.

"As for whether he will resign, no, he has made it very clear he is staying there and is going to try and fight this through and get agreement with this bailout package that will save Greece from bankruptcy without having to go down the route of referendum."

Greek crisis dominates G20

The drama has also dominated the G20 meeting in Cannes, where the leaders of the world's economic powerhouses have gathered to tackle Europe's debt crisis, which threatens to push the world back into recession.

CTV's Robert Fife, reporting Cannes, said the dramatic events of the day had politicians and reporters unsure of what would come next.

"It was like watching a car race that might turn into a car wreck," Fife reported, adding that the stakes remain high for all of the 17 nations that make up the Eurozone and the G20.

The key problem for the leaders now is to draft a real plan to dismantle the ticking debt bomb, and Fife said that simply issuing a "blank reassurance" won't be enough to calm skittish global markets.

While the Greek imbroglio needs to be solved immediately, Fife said that Italy -- Europe's third-largest economy -- also needs to take definitive action on its own debt problems.

With files from The Associated Press