Officials from European Union and International Monetary Fund lenders met Greece's finance and economy ministers in Athens on Saturday, the day after EU finance officials held a teleconference and noted progress in the talks.
The talks on Saturday focused on the so-called "prior actions" Greece must legislate to qualify for loans, and the two sides reached agreement on the issue, a senior government official said without giving details.
Talks will continue on Sunday to discuss more contentious issues, the official said.
"The agreement will be concluded comfortably before Aug.18," the official said.
Greece narrowly dodged a euro zone exit last month after months of acrimonious negotiations that culminated with Prime Minister Alexis Tsipras clinching a deal tied to stringent austerity and reform terms to avoid economic collapse.
Since then negotiations on the agreement itself - which will spell out details of the reforms and funds to be disbursed - have proceeded remarkably smoothly, with the lenders praising Greece for its cooperation.
The view of EU officials on Friday's conference call was that talks are proceeding well and may be completed over the weekend, one source familiar with the matter said.