The stock market rallied on Monday, with benchmark indexes on the European markets surging over 9 percent and U.S. stocks adding around 3.9 to 4.8 percent.

But analysts say it remains to be known how Greece, with the EU statistical agency forecasting a contraction of 3 percent this year for its economy, will be able to sustain its rolling government debt.

The debt crisis is partly attributable to the expansionary fiscal policies adopted by many governments worldwide to finance the bid to save their banking system amid the global financial crisis, Zhu Min, a special advisor to IMF chief Dominique Strauss-Kahn, said earlier this year.

"The debt pressure for the developed countries will peak in 2012," he said in April before assuming office at the International Monetary Fund.

The Center for European Policy Studies estimates that the debt-to-GDP ratio of Greece will rise to 150 percent in 2013 if the rescue plan is materialized, meaning that normally 6 percent of Greek GDP will have to be used to sustain the debts.

Greece is certainly not the only debt-troubled economy. Statistics show that governments worldwide have borrowed a total of 35 trillion U.S. dollars, with some of the developed countries running fiscal deficits of above 10 percent, which are way above the internationally recognized red line of 3 percent.

The overall fiscal deficit in 2009 was 6.3 percent of their combined GDP, and the debt-to-GDP ratio was 78.7 percent, higher than the European Union's cap of 3 percent and 60 percent, respectively, according to the EU statistical agency.

The rescue package also came with prerequisites that governments of these countries push through austerity measures. European policy makers called for tough and even unpopular reforms in the wake of the Greek debt crisis.

"A decade of austerity will be necessary," Vincent Van Quickenborne, Belgian minister of economy and reform, said at a forum Tuesday.

But this could lead to medium- to long-term risks as the fiscal tightening could dampen the economic recovery in the eurozone, economists say.

The fallout from the Greek debt crisis will definitely impact the still weak recovery in Europe, said Hong Pingfan, head of the global economic monitoring center of the UN Department of Economic and Social Affairs (DESA).

The massive aid package also will lead to a weaker euro in the medium- to long-term, he added.

The imbalances in the Greek economy, caused by excessive consumption, remain to be addressed. "Any deleveraging by households could add to the economic pressures especially in those markets where the banking system is also attempting to reduce leverage," Moody's said in a recent report on the contagion risks in Europe.

Greece shall not benefit much from the rescue, whereas defaults will lead to increased debt pressure on other economies via indebtedness, said Zuo Xiaolei, chief economist of China Galaxy Securities.

The dilemma exposed the weakness of the eurozone, where member states can have their own fiscal but not monetary policies. EU leaders on Wednesday pushed for fiscal discipline but stopped short of intervening in the member states' fiscal policies.

The silver lining is that the EU leaders have been calling for reforms, including changes to the "extravagant European social welfare system."

Roubini also sees a possible outcome that the 440 billion euros in guarantees could eventually develop into a full-fledged European Monetary Fund.

He even proposed a preemptive debt restructuring for Greece via extending the maturity of the country's bonds, with the money pledged by the EU and IMF used to stave off an interbank run or contagion to other countries.