The representatives of Greece's private creditors left Athens unexpectedly today without a deal on a debt swap plan that is vital to avert a disorderly default.
Negotiations will continue over the phone during the weekend, but it is unlikely that an agreement can be clinched before next week.
A lot of progress has been made on the details of the plan during talks between Athens and Institute of International Finance chief Charles Dallara, but any deal needs the approval of the IMF and eurozone countries, who insist on a substantial cut in the debt load.
The IMF and EU countries, and in particular Germany, want to make sure the deal puts Greece's derailed finances back on a sustainable track before they agree to a new €130bn bailout, which is also crucial to avoid a messy default.
The IMF insists the debt swap deal must ensure Greece's debt burden will be cut to 120 % of GDP by 2020 from 160% now, as agreed at an EU summit in October
The IMF has warned that this is made more difficult by the fact that Greece's economic prospects have deteriorated since.
"Things are complicated, we are getting closer on the numbers but there is still quite some work ahead," one source close to the talks said.
"Discussions will continue over the phone this weekend but an agreement is unlikely before next week, if there is an agreement at all."
A meeting Monday of eurozone finance ministers will be crucial for the debt swap talks.
