Stock markets were on edge today as a make-or-break moment for the eurozone at a general election in Greece approaches.
Success for anti-austerity parties, such as radical left-wingers Syriza, could lead to Greece leaving the euro, which would likely send stock markets into freefall.
A Greek exit from the euro could lead to contagion across the eurozone and beyond as the impact of a collapsed banking system and debt default in Greece spreads like a domino effect.
As the pivotal event approaches, speculation is mounting that central banks, including the Bank of England, Bank of Japan and US Federal Reserve, are preparing to launch emergency support measures to cushion the blow of an implosion in the eurozone.
In London, the FTSE 100 Index held up after the Bank of England and the Treasury cheered investors with plans for a multi-billion pound scheme to boost lending.
But analysts warned that this would be a temporary lift as the Greek election inched closer.
Kathleen Brooks, research director at Forex, warned: "There is one thing on the markets' minds and one thing on global policymakers' minds at the moment - will Greece manage to stay in the eurozone?"
The Greek election is being held against a backdrop of increased economic turmoil across the eurozone, with the likes of Spain and Italy seeing their borrowing costs soar as investors lose faith in the countries' abilities to control their finances.
A first election in Greece on May 6 produced a hung parliament, with Syriza a surprise runner-up to pro-bailout terms party New Democracy, but days of negotiations failed to deliver a coalition agreement, forcing this Sunday's election.
The latest official polls released showed that either New Democracy or Syriza could win on Sunday, although without enough seats in parliament to govern alone.
The polls, however, suggested that in either case the winner would be able to secure enough support from like-minded parties to form a coalition.
Greece has had to adopt a range of far-reaching austerity measures as a condition of receiving rescue loans from the European Union and International Monetary Fund.
The Greek people have reacted angrily to the conditions, fuelling a surge in popularity for political parties like Syriza that want to renege on the country's bailout terms.
Without the EU bailout cash, Greece would go bankrupt and likely have to leave the 17-country bloc.
However, Syriza leader Alexis Tsipras has insisted that he could scrap Greece's bailout commitments while keeping the country in the eurozone.
Aged only 37, Tsipras is one of the youngest politicians in the country, and one of the most popular. He is the icon of the Greek anti-austerity movement, uniting the frustrated, the desperate, the poor and the outraged together to try to turn the country around through means other than budget cuts.
A result for either a pro-bailout or anti-austerity party is likely to lead to volatility on markets next week, analysts warned.
Shavaz Dhalla, financial trader at Spreadex, said: "Next week's economic agenda however is likely to provide a rollercoaster ride for investors, as the results of the Greek elections over the weekend will either play havoc or provide a basis of euphoria for investors."
The euro was down against most major currencies ahead of the election, while the US dollar, seen as a safe haven investment in times of economic volatility, rose in value.
Likewise, gold, also seen as a safe-haven investment, rose to 1623 US dollars an ounce, while the cost of Brent crude oil slipped 0.2% to under 100 US dollars a barrel.