Iranian Foreign Ministry Spokeswoman Marziyeh Afkham announced that Iranian negotiators are due to take part in a quadrilateral meeting with the three European members of the Group 5+1 in Vienna on September 11.
"We will hold talks with the European countries at the end of this week and as we have agreed, there will be a ministerial meeting with the Group 5+1 on the sidelines of the UN General Assembly meeting (in New York on September 20)," the Iranian foreign ministry spokeswoman  told reporters on Monday.
She noted that Iran has always reiterated that the nuclear talks should bear results and it is doing its best to this end.
Iran and the six world powers are currently in talks to work out a lasting accord aimed at ending the longstanding dispute over Tehran’s civilian nuclear activities.
Last November, the two sides signed an interim deal in Geneva, which took effect on January 20 and expired six months later on July 20. In July, Tehran and the six countries agreed to extend negotiations until November 24 after they failed to reach an agreement on a number of key issues.
On September 1, Iranian Foreign Minister Mohammad Javad Zarif and EU foreign policy chief Catherine Ashton met in Brussels, Belgium, and discussed the process of the ongoing nuclear talks for more than three hours.
After his negotiations with Ashton, the Iranian foreign minister said he was optimistic that issues related to the Iranian nuclear technology could be resolved within the time framework of the November 24 deadline.
Then, senior Iranian and US negotiators had three days of talks in Geneva from Thursday to Saturday.
Following the talks, Iranian Deputy Foreign Minister Majid Takht Ravanchi said the talks in Geneva were "much useful" and were aimed at making preparations for the multilateral talks between Tehran and the six world powers in New York on September 18.
"These meetings were aimed at making preparations for (the upcoming) New York meeting," Takht Ravanchi, also a senior negotiator in Iran's nuclear talks with the world powers, told FNA on Sunday.
He assessed the three-day-long talks in Geneva as "much useful", saying the meetings were good because "we could go into more detailed issues".
"We expressed our different stances in these sessions and discussed with the other side the subjects that were negotiable," he said, adding that the two sides laid emphasis on issues that had been discussed in their previous meetings.
Another Iranian Deputy Foreign Minister and senior negotiator, Seyed Abbas Araqchi, had also earlier described the bilateral talks with the US over a final nuclear deal in Geneva as "useful".
"The negotiations which will continue tomorrow (Saturday) have been useful so far and we hope that they can help resolve the differences," Araqchi said on Friday.
Noting that the two sides still have some differences, he said, "God willing, we will make progress by September 18, when the next round of the negotiations between Iran and the Group 5+1 (the US, Russia, China, Britain and France plus Germany) will be held in New York."
Araqchi and Takht Ravanchi held bilateral talks with their US counterparts Wendy Sherman and William Burns in the Swiss capital from Thursday to Saturday.
The negotiations between Araqchi, Takht Ravanchi, Sherman and Burns took place within the framework of the talks between Tehran and the Group 5+1.
No details have yet been released on the exact contents of the talks.