The chief negotiators for Greece's private creditors have left Athens without securing a deal to write off some of the country's debts.
The Institute of International Finance, which represents the creditors, says a technical team will remain to work on the details and negotiations would continue on the phone.
Greece had hoped an agreement would be in place by the end of the weekend. It needs a deal if it is to receive the next tranche of bailout funds.
Another 130 billion euros from the European Union and International Monetary Fund is crucial if Greece is to meet its next debt repayment deadline in two months.
The institute denied that managing director Charles Dallara and his adviser had left unexpectedly on Saturday, saying they had longstanding personal appointments.
A deal now seems unlikely before eurozone finance ministers meet on Monday.
It's been reported Greece and its private creditors had been inching towards a deal in which private creditors would take a real loss of 65% - 70%.