In a tweet on late Thursday, Mikhail Ulyanov wrote, "I believe that the negotiators are not exhausted but they are a little bit tired."
"It is obvious that the #ViennaTalks will require additional time to complete successfully this lengthy and rather complicated process," he added.
The Russian diplomat has previously described the process of reviving the JCPOA positive.
"The #ViennaTalks are getting progress. Over the last couple of days, we achieved more clarity with regard to one of the most controversial issues-Implementation plan (who should do what and when). However, some difficult and time-consuming topics still remain unresolved," he wrote in a tweet.
Speaking in an interview with Al Jazeera on Thursday, the Iranian Deputy Foreign Minister for the Political Affairs Seyyed Abbas Araghchi said that Iran’s nuclear deal, JCPOA, is still alive thanks to Iran’s cooperation with the remaining parties to the deal.
“We have made good and tangible progress on various issues in Vienna talks, he said regarding the negotiation process, adding, "We believe that we are closer to an agreement than ever before, but there are still some fundamental and key issues that need to be negotiated.”
The 6th round of the Joint Commission meeting of the Joint Comprehensive Plan of Action (JCPOA) was held in Grand Hotel Wien in Vienna on Saturday in presence of delegations of Iran and P4+1 (Germany, France, Russia, China and UK).
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