Greece's government started talks on the terms of a third Greek bailout with creditors' envoys in a "positive climate," Greek Finance Minister Euclid Tsakalotos said Friday.

"We agreed on some issues, we disagreed on others, but the discussion was made in a very positive climate and will be continued," he said after a first meeting with the mission chiefs of the four institutions representing Greece's lenders (European Commission, European Central Bank, IMF and European Stability Mechanism).

Tsakalotos and Economy Minister Yorgos Stathakis discussed issues such as the recapitalization of Greek banks after capital controls, the structure of a new privatization fund and fiscal adjustment.

Tsakalotos said the two sides talked about how to reach a primary surplus of 3.5 percent of GDP in Greece by 2018.

The informal meeting took place in the hotel where the foreign envoys are staying because the Greek side wanted to avoid publicity.

Athens hopes to finalize the third bailout by Aug. 20, when the country needs to repay a loan installment to the European Central Bank.

However, many analysts expect that the goals will most likely not be reached and a new bridging loan will be granted to the country until a final agreement is sealed.

Prime Minister Alexis Tsipras also seems to have won some more time in regards to the internal wrangling within his ruling radical left Syriza party over the third bailout which has fuelled worries over a possible government collapse.

The Greek leader also suggested a referendum for Syriza party members as soon as this Sunday to decide the future course, in case the government's critics within the party were "in a hurry" to sort out differences over the deal and in general the government's policies.

The central committee eventually decided to hold a party congress in September.