Greece failed again to clinch a deal with its international creditors on June 25, setting up a last-ditch effort on June 28 to avert a default next week or start preparing to protect the euro zone from financial market turmoil.
Euro zone finance ministers ended their third meeting in a week without agreement after the three creditor institutions put a final cash-for-reform proposal on the table in a showdown with Athens's leftist government.
German Chancellor Angela Merkel, whose country is Greece's biggest creditor, said the next meeting of Eurogroup ministers on June 28 would be "of decisive importance" for a Greek solution since time was running out.
She declined to speculate about what would happen if there was no deal but said government leaders could not intervene in the complex negotiations, and there was no new money beyond what was left in Athens' frozen bailout program.
Without a deal at the weekend to unlock frozen aid, Greece, which has received two bailouts worth 240 billion euros since 2010, is set to default on a crucial repayment to the International Monetary Fund on July 1.
That could trigger a bank run and capital controls, possibly setting Athens on a path out of the euro zone and undermining the founding principle that membership is irrevocable.
"The door is still open for the Greek side to come with new proposals or accept what is on the table," Eurogroup chairman Jeroen Dijsselbloem told reporters before briefing European Union leaders, meeting at a summit next door, on the impasse.
Greece thrust its way onto the agenda of a 28-nation EU summit that had been due to focus on migration, the long-term future of the euro zone and launching a renegotiation of Britain's membership terms.
The leaders spent two hours on an unscheduled discussion of the crisis, appealing to Prime Minister Alexis Tsipras to accept the proposals on the table and spare the Greek people worse suffering, EU officials said.
Tsipras urged fellow leaders to take responsibility and not leave Greece's fate in the hands of the International Monetary Fund, but they declined to step in, saying the talks must be run by finance ministers, the officials said.
