The ministers gave the debt-ridden country until the middle of next week to find an extra euro325 million ($430 million) in savings, pass the cuts through a divided parliament, and get written guarantees that they will be implemented even after the elections of a new government in April, said Jean-Claude Juncker, the Luxembourg prime minister who chaired Thursday's meeting of finance chiefs of the 17 euro countries.

The new austerity plan, which makes sharp cuts to the minimum wage and thousands of public-sector jobs, ignited fresh criticism from unions and the country's deputy labor minister, who resigned in protest after Greece agreed to the deal. Even debt inspectors conceded that the new measures would keep the country in a recession for a fifth straight year.

But Greece's finance minister warned that the alternative will likely be worse.

"Unfortunately the choice we face is one of sacrifice or even greater sacrifice - on a scale that cannot be compared," Evangelos Venizelos told reporters, after the meeting with ministers from the 16 other countries that use the euro.