The mechanism would be activated if Greece were unable to finance itself on the market despite the country's austerity measures.
The ministers from the so-called Eurogroup said the mechanism would not give Greece financing at average euro zone rates but aim to make it return to markets as soon as possible.
The member states of the euro area will take coordinated action if such action turns out to be necessary. We clarified the technical arrangements ... to take coordinated action, Eurogroup Chairman Jean-Claude Juncker told a news conference.
The ministers from the 16-country currency bloc said in a statement: It (the Eurogroup) clarified the technical modalities enabling a decision on coordinated action and which could be activated swiftly in the case of need.
(Reporting by Brian Love, Marcin Grajewski and Jan Strupczewski, editing by Dale Hudson)