Tehran rejected a key Western demand for site inspections Saturday as top US and Iranian diplomats began a major push to conclude the agreement.
A month away from a nuclear deal deadline, US Secretary of State John Kerry and Iranian counterpart Javad Zarif met for six hours in Geneva, the first high-level negotiation round since Iran struck an interim accord with United States, Britain, France, Germany, Russia and China (P5+1) on April.
A senior Iranian negotiator said the two sides failed to bridge differences between Tehran and the P5+1 world powers.
“The differences are still there,” Abbas Araghchi, deputy head of Iran’s negotiating team said following the closed meeting.
While world powers push for international access to Iran’s military sites, Iran wants sanctions to be lifted immediately after a deal is reached.
Araghchi also warned that the deadline may need to be extended.
The United States has said it will not extend the talks beyond the June 30 deadline.
But France, which has demanded more stringent restrictions on the Iranians, has indicated discussions are likely to slip into July.
“Secretary Kerry and Foreign Minister Zarif, along with their teams, had a thorough and comprehensive discussion of all of the issues today,” a senior US State Department official said, without elaborating.
After three decades of enmity, an accord would pave the way to bringing Iran back into the international fold and create a fresh impetus to resolve a host of conflicts in the Middle East. The Geneva meeting came as the United States and its partners - Britain, China, France, Germany and Russia - seek to finalise the complex pact.