(MarketWatch) — European finance ministers agreed late Sunday on a rescue package worth as much as 500 billion euros ($670 billion) designed to keep the Greek debt crisis from spreading to other vulnerable countries. 
The deal came after a full day and night of closed-door meetings in Brussels. The finance ministers held a joint press conference shortly after the opening of Asian markets — well after midnight local time — to discuss the program.
European ministers also hit back at speculation that the euro zone would be forced to shrink if the crisis continued.
“We shall defend the euro whatever it takes,” said Olli Rehn, the European Union’s commissioner for economic affairs.
The package was designed to ease market fears that Greece, Portugal or Spain will have to restructure their debt, a move that would have hit European banks particularly hard.
Rehn said the European Central Bank had agreed to buy government bonds in the secondary market to support the program.
The International Monetary Fund will also contribute to the plan, perhaps by as much as 250 million euros, the EU officials said.
