Greece's finance minister said on Sunday aid would arrive fast enough to avert a debt default as signs grew that a 45 billion euro ($60.49 billion) rescue package would have to be increased.

Finance Minister George Papaconstantinou said bailout talks with the International Monetary Fund and European partners had gone well, and he was confident Greece would secure help in May to finance its crippling public debt without any problem.

At a press briefing at the IMF in Washington, he downplayed concerns that Germany might stand in the way of a rescue deal that is hugely unpopular in Europe's biggest economy.

Even if there were delays in getting parliamentary approval in some European countries, IMF support could be matched with bridge loans from other European countries that had already cleared the deal, he said.

IMF and European funding would be disbursed simultaneously, he said.

The IMF is expected to provide one-third of the aid.

Papaconstantinou also sent a warning to investors who have been betting that Greece will default on its debt: All I can say is that they will lose their shirts.

Saddled with huge debt and a swollen deficit, Greece bowed to intense pressure from financial markets on Friday and formally requested aid, triggering what would be the first bailout of a member of the 11-year-old single currency bloc.

Athens has already announced billions of euros in budget cuts, including tax hikes and reductions in public sector wages, but is now in talks with the European Union and IMF on additional steps to get the aid flowing.

IMF Managing Director Dominique Strauss-Kahn issued a statement on Sunday saying those talks had accelerated and expressing confidence in Greece's determination to get its economy back on track.

Canada's Finance Minister Jim Flaherty said the package would end up being more than had been said previously, declining to specify the amounts being discussed.

Asked by a reporter whether aid could be as much as 80 billion or 90 billion euros, Papaconstantinou said he could not provide specific figures.

French Economy Minister Christine Lagarde pointed out that the 30 billion-euro commitment from the Eurogroup was just for the first year of a three-year package and talks were going on about what would come after the first year.

GREECE PLEDGES TOUGH MEASURES

German Finance Minister Wolfgang Schaeuble warned Greece that a tough restructuring of its economy was unavoidable and an absolute prerequisite if Berlin and the EU were to approve the aid Greece has requested.

Papaconstantinou said Greece was already taking tough measures at home and the aid package would include strict conditions.

He said Germany was completely on board on the need for a framework of conditionality and fully supportive of a decision that Germany has co-signed at the level of heads of state and government and at the Euro group level.

France's Lagarde promised to hold Greece accountable for unsuitable economic policies that pushed its 2009 budget deficit to 13.6 percent of gross domestic product and its debt to 115 percent of output.

She described the aid package as a cocktail of indulgence and great strictness, telling the Journal du Dimanche weekly that Greece's partners would closely monitor progress and put their foot on the brake if Athens reneged on commitments.

Germany and France, the biggest economies in the 16-nation euro zone, are due to provide about half of the 30 billion euros in aid that the EU has tentatively pledged for Greece in the first year of its program.

DOUBTS ON AID PACKAGE

Only days after Greece requested the rescue funding, doubts were already emerging over whether the package was large enough to calm market fears of a debt default.

Those fears have pushed the yield on Greek 10-year bonds above 8.7 percent, a whopping 567 basis points over the rates on benchmark German Bunds.

This has made it prohibitively expensive for Athens to service its mountain of debt. Greece's formal request for aid on Friday did little to ease market pressures.

Papaconstantinou said he understood markets still needed to be convinced that the aid would be secured fast enough and Greece would follow through on its commitments.

One big risk to Greece's economic plans is public opposition to further austerity steps. Greek riot police fired teargas at protesters who held an impromptu march through central Athens on Friday to protest against more budget cuts.

A poll released on Saturday showed that roughly two-thirds of Greeks believe Prime Minister George Papandreou's socialist government was either too slow to react or handled the economy poorly as the country's fiscal crisis deepened.

Center-left newspaper Eleftherotypia said the specter of Hungary was haunting Papandreou's government. Voters in Hungary booted out the socialist government this month after it tried to push through painful IMF-ordered budget cuts.

(Additional reporting by Noah Barkin in Berlin, Sophie Hardach in Paris, George Georgiopolous in Athens, Tracy Rucinski in Madrid; Writing by Emily Kaiser and Noah Barkin; Editing by Ralph Boulton)

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