Greece hopes to close a deal with international creditors on a multi-billion-euro austerity package in about a week, a senior finance ministry source said on Friday.
The official, speaking on condition of anonymity, said talks would continue on identifying 11.5 billion euros ($15 billion) in savings and a further 2.0 billion euros in revenue that are necessary to unlock an EU-IMF loan instalment.
"We are trying to finalise the package worth 13.5 billion euros (overall)," the official said.
"Progress has been made...there are still elements that need to be investigated and clarified," he said.
The finance ministry had earlier indicated that a deal was within reach on Friday, though an EU official said on Friday that the decision to take a break was in the works for "some time" and was "not an indication that there are problems."
Greece is thought to need to identify another two billion euros worth of measures to reach agreement with its creditors.
In a joint statement, the IMF and European Commission said that their mission in Athens, working alongside experts from the European Central Bank, would take a "brief pause."
The mission "expects to return to Athens after about a week," the statement said.
"During this period some mission experts will remain in Athens to assist the authorities with further technical work, while contacts will continue with the authorities from respective headquarters," the creditors said.
The heads of the so-called 'troika' mission would leave and return, the Greek official said.
"The technical team will remain so that when (the supervisors) return we will have closed the list," he said.
Greece is supposed to meet key targets under its adjustment programme in return for European Union and International Monetary Fund bailout funding.
A loan instalment of 31.5 billion euros is pending, needed by Athens to pay state salaries and pensions, recapitalise Greek banks hit by a state debt rollover and repay over six billion euros owed to private contractors.
The fiscal programme is supposed to run to 2014, but Greece wants this deadline extended to 2016.
A European Union summit on October 18 and 19 is expected to decide on the Greek request.
Speaking to fellow members of the Centrist Democrat International political movement in Rome on Friday, Greek Prime Minister Antonis Samaras said his country could "grow out" of its problems and that leaving the euro would be a "nightmare."
"Greece can "grow out" of its problems," Samaras said.
"It has all the potential and the competitive advantages, the resources and the assets - human and material - to make a spectacular come back."
"An exit from the euro-zone is not a choice for Greece; it is nightmare," the Greek premier said, warning that such a development would hard on eurozone peers also as "world speculators" would then turn on the "next weakest link" in the single currency area.