"[The meeting] will definitely be held before New Year's, and it won't be in Vienna. A date after the 20th [of December] would be too late because of the West's Christmas [season]. I think it will be before December 20," Ryabkov said.
According to Ryabkov, Former EU Foreign Policy Chief Catherine Ashton is confirmed again as a special adviser and will continue to coordinate the talks.
"As you have seen, the European External Action Service said that [EU foreign policy chief Federica] Mogherini is going to personally participate in the events that will be held on the ministerial level," deputy foreign minister added.
"All this, in our view, demonstrates the determination not to lose the tempo and dynamics and to complete what was brought to a high degree of readiness, but has not been totally settled. We [Russia] will participate in it with full responsibility, as we did before," Ryabkov stressed.
Tehran has been a target of sanctions imposed by the UN Security Council, as well as the European Union, the United States, and several other countries over allegations that Iran is attempting to produce nuclear weapons under the guise of a civilian nuclear energy program.
These claims have been repeatedly denied by Tehran officials, who state that Iran's nuclear development is peaceful in nature and aimed purely at satisfying the country's energy needs.
Last year, Iran and the P5+1 group of international mediators comprising Russia, the United States, the United Kingdom, France, China and Germany committed to an agreement with a July 2014 deadline. The deadline was later extended to November 24.
After heated negotiations the November 24 deadline passed without an agreement and all parties stated their intention to continue the dialogue, setting a new deadline of July 2015.