The second round of negotiations on Tehran’s nuclear program between Zarif and Ashton has ended as a meeting between Zarif and his Russian counterpart Sergey Lavrov has begun.

The second round of negotiations on Tehran's nuclear program between the Iranian FM Mohammad Javad Zarif and EU foreign policy chief, Catherine Ashton has ended as a meeting between Zarif and his Russian counterpart Sergey Lavrov has begun.

Zarif said that the Islamic Republic will not negotiate its right to uranium enrichment.

"Iran stands on its nuclear rights firmly, and the recognition of Iran's uranium enrichment right will be part of any deal which might be struck between the country and the six world powers," he added.

A senior Iranian diplomat said Friday nuclear negotiations in Geneva with world powers were moving closer to an accord after progress was made on the third day, media in Tehran reported.

"To a good degree, we have moved (closer) towards agreement," deputy foreign minister Abbas Araqchi told reporters, according to the Mehr news agency.

But he added, without elaborating, that despite "progress made today, some main issues still remain" in the diplomatic push to end a decade-long dispute over Iran's controversial nuclear drive.

US Secretary of State John Kerry was Friday heading to Geneva to help bridge gaps in talks with Iran as negotiators grapple for a deal to rein in its nuclear program.

US officials said Friday it still hopes the Geneva talks will reach an accord on Iran's nuclear activities, but stressed the talks were "tough and challenging".

And Psaki said Kerry's decision to fly to Geneva was "not a prediction of the outcome."

"We hope that an agreement can be reached," White House spokesman Jay Carney said before Kerry's travel was announced.

"The Iranians decided they were not able come to an agreement in the previous round, but we remain hopeful that we can reach an agreement with all of our P-5 plus one allies and the Iranians in Geneva."

The comments in Washington came amid upbeat reports from Geneva, where Iranian negotiators said progress was being made, with the talks now in their third day.

Russia's Foreign Minister Sergei Lavrov flew to Geneva, in a fresh push to clinch a deal.

Psaki said "there are tough issues on the table" and the negotiating teams had decided to narrow down the meetings to include just Ashton and Iranian Foreign Minister Mohammed Javad Zarif.

"That's something that we have encouraged because it is more efficient and effective to have one-on-one negotiations instead of seven delegations around a table. It's further indication of how unified the P-5 plus one is," Psaki told reporters.

The "negotiations are fluid, our sleeves are rolled up, we're knee-deep in the negotiations," Psaki said, adding that Kerry believed in "personal diplomacy" and that "face-to-face negotiations are effective."

A western diplomat said Group 5+1 has accepted Iranˈs right for uranium enrichment, IRNA had previosly reported.

The diplomat, who asked not to be named, told IRNA that Iran and Group 5+1 have finalized their discussions on uranium enrichment by accepting Iranˈs right in the final document.

He continued that the two sides are discussing Arak Heavy Water Reactor now.

Foreign Minister Mohammad-Javad Zarif told reporters here on Friday that many of issues are being solved.