Sergei Ryabkov said six world powers and Iran had never been so close to an agreement and it could be reached by a Nov. 24 deadline.
"Therefore, from (Nov.) 18 to 24 there is enough time for such decisions to be taken," he told reporters on the sidelines of G20 summit in Austria.
"But there is no guarantee that these decisions will be taken in those capitals where there are the biggest problems with current solutions, I mean, - Washington and Tehran," the Russian senior diplomat reiterated.
Iran and the Group 5+1 (Russia, China, Britain, the United States, France, and Germany) will meet in Vienna from November 18 to try to seal a long-term agreement on Tehran’s civil nuclear program before a November 24 deadline.
On November 24, 2013, Iran and the G5+1 (alternatively known as P5+1 or E3+3) signed an interim nuclear deal in the Swiss city of Geneva.
The Geneva deal (the Joint Plan of Action) came into effect in January and expired in July, when the parties decided to extend negotiations until November 24 in the hope of clinching a final, lasting accord.