George Papandreou, the Greek prime minister, faces a crucial no-confidence vote on his leadership following a week of turmoil.

Should he lose the viability of ruling socialist party to continue in government looks uncertain.

Even if he wins the vote, reports suggest that Papandreou may still resign.

The vote is expected to take place at 10pm GMT. The timing of the vote is designed to cause the least impact on European and US markets.

The vote follows days of uncertainty as the prime minister announced a shock referendum on the eurozone bailout.

On Thursday, following pressure from eurozone leaders meeting at the G20 summit in Cannes, the referendum was scrapped, leading to a chorus of calls for Papandreou to quit.

Outside the parliament in Athens, thousand of protesters have gathered, many from the Greek Communist Party.

The uncertainty in Athens has overshadowed the efforts to tackle the European debt crisis by world leaders in France, with questions over Papandreou’s leadership, alongside the country’s continued involvement in the eurozone project, causing havoc with global markets.

The socialist Pasok party holds a small minority in parliament (152 out of 300 seats) with several members of the party openly admitting that they will vote against the Greek PM.

However, with the threat of the government collapsing many in the chamber have stated the importance of voting in favour of Papandreou.

I do not want to humiliate my party's president – the country's prime minister – by toppling him tonight,” said Telemachos Hytiris, a government spokesman.

“But I want him to rise to the occasion as a prime minister who has won the vote of confidence with prestige and start discussions tomorrow on a unity government so the country can move forward.”

On Thursday Antonis Samaras, the leader of the conservative New Democracy opposition party, called for the bail out to be agreed and for a snap election, in which his party is likely to win the most seats.

"I'm asking for the formation of a temporary, transitional government with an exclusive mandate to immediately hold elections. And the ratification of the bailout deal from the current parliament," he said.

This morning Greek finance minister Evangelos Venizelos formally told EU leaders gathered in Cannes that the referendum had been cancelled.