A German Finance Ministry spokesman told a regular government briefing there were still outstanding questions over an escrow account for debt repayments, surveillance of policy, financing gaps and debt sustainability.
Officials were likely to continue hashing out details until Sunday, said Martin Kotthaus.
"I assume that we will have a solid basis on Monday, from which the ministers will then be able to take a joint decision. This is all positive of course," he said. "However, it is still too early to say how the decision might turn out."
Eurozone leaders have been negotiating a Greek rescue package of €130 billion and a write-down of privately held government bonds worth €100 billion to avoid Greece defaulting on its debt package that comes due as early as next month.
After a conference call between the leaders of Germany, Italy and Greece, the Italian government released a statement saying officials were “confident” a deal would be reached to take pressure off Greece.
Meanwhile police continued to struggle to keep protests in Athens under control. They briefly detained then released eight Germans protesting outside the embassy on Friday after someone threw an egg at the building.
German activist group Schwabingrad Ballet held up placards saying "Greece selloff – not in our name" and "No to this memorandum," a reference to the EU-IMF fiscal adjustment applied in Greece.
Germany has been leading the call for tighter austerity measures in Greece arousing public anger and animosity which has reached unprecedented levels.