The 90-minute talks started at 09:00 local time between the two sides.

Foreign Minister Mohammad Javad Zarif, US Secretary of State John Kerry, Russian Foreign Minister Sergei Lavrov, German Foreign Minister Frank-Walter Steinmeier, French Foreign Minister Laurent Fabius, Chinese Foreign Minister Wang Yi, British Foreign Secretary Philip Hammondn, and EU High Representative Federica Mogherini were present in the meeting, IRNA reports.

Iranian Deputy Foreign Minister Abbas Araqchi said Sunday that no deal on the Iranian nuclear program has been struck yet but many issues have been resolved.

'There is no deal yet, but we have found solutions to many issues,' Araqchi said.

Iran demands that all sanctions and UN resolutions imposing restrictions against Tehran be scrapped as part of its nuclear deal with major world powers, Araqchi noted.

Although AFO reporting Russian Foreign Minister Sergei Lavrov will leave nuclear talks with Iran in Switzerland and return the following day if there a realistic chance of a deal, but Ryabkov his deputy said Talks intensive and allow for optimism.