Greece's plan to buy back bonds from private investors under Tuesday's Eurogroup deal must work, since it ensures the country's stay in the eurozone, Greek Finance Minister Yannis Stournaras said on Wednesday.

The scheme is part of the new set of policies European Union (EU) and International Monetary Fund (IMF) lenders agreed on in order to further reduce the Greek sovereign debt load and assist Greece's efforts to counter the severe debt crisis.

The success of the plan, which is scheduled to be launched next week and be completed within a few days, is a precondition for the release of the fresh 44-billion-euro (57-billion-U.S. dollar) bailout tranche to Athens in coming weeks, which is vital to avoid a disorderly bankruptcy which could destabilize the entire eurozone.

Some 34 billion euros will be disbursed by Dec. 13 to be used for the recapitalization of Greece's banking sector and the financing of the real market, Stournaras explained during a press briefing in Athens on the results of Eurogroup meeting. The rest will be released in three installments until next spring.

"We can say that it is a very important decision which paves the ground for our stay in the eurozone and offers us a significant opportunity to exit the vicious circle of over-indebtedness and recession," he said.

The bond buypack plan, which is voluntary like last March's 100-billion-euro write-down, he stressed, will contribute to the reduction of the country's debt burden by 20 percent of GDP in the next decade and its sustainability.

"It must work. The success is a matter of credibility for our country," Stournaras stressed.

He did not give many details on the scheme, since some elements have not been finalized. However, he underlined that its 13-14-billion-euro funding, which is not included in the next tranche, is assured through revenues expected from the country's privatization program.

According to local analysts' estimates, some 30 billion euros' worth of bonds held by private investors could be purchased at a discount. Their value has decreased since the start of the debt crisis in late 2009 and March's debt swap.

The Greek official warned that despite the latest positive developments, much remain to be done in coming months and years.

"The tough period begins now. It is time for us to think how we are going to make the best of this great chance which Greek citizens won with their sacrifices and our partners in the EU and IMF granted to us," he said.

He stressed that Greece needs to accelerate the implementation of the structural reform part of the wider stability and development program in order to return to growth as early as possible to exit the crisis.

Since 2010, Greece has been kept afloat with multi-billion-euro international rescue loans in exchange of a painful austerity and reform program which has missed initial targets and timetables due to deep recession, a deteriorating international financial environment and other factors. (1 euro = 1.29 U.S. dollars) Endi