Finance ministers for the 19-nation common currency union approved the first tranche of an 86 billion euro package, the third such emergency deal in five years.
The approval came despite a rebellion within the ranks of the ruling leftist party over harsh austerity measures imposed in exchange for the $93 billion deal.
Yanis Varoufakis, who was forced to resign as a condition for concluding a financial rescue deal, says the latest austerity program will "go down in history" as a disaster.
With the bailout package that has kept Greece's economy afloat set to expire in just over a week, the country has formally asked Eurozone members for a six-month extension.
The leftist Syriza party, which has vowed to roll back EU-mandated austerity measures, have edged out the ruling center-right party of Prime Minister Antonis Samaras.