Iran’s talks with six major powers on curbing its nuclear program in exchange for an end to sanctions could be extended for another six months if no deal is reached by a July 20 deadline, a senior Iranian official said.

While an extension is possible, experts believe both sides may come under pressure from critics at home to seek better terms during this extra time period, further complicating negotiations.

Singling out a big gap in negotiating positions that will be difficult to overcome in less than two months’ time, France’s foreign minister said Iran should drop a demand to have thousands of uranium enrichment centrifuges. Instead it should restrict itself to a few hundred of the machines used to increase the concentration of the fissile isotope.

Iran – which says its nuclear program is peaceful and rejects accusations it has been seeking to develop a nuclear weapons capability – now has around 19,000 centrifuges installed, of which roughly 10,000 are operating, according to the U.N. nuclear agency. Enriched uranium can have both civilian and military uses, depending on the degree of refinement.

“We are still hitting a wall on one absolutely fundamental point which is the number of centrifuges which allow enrichment,” Laurent Fabius told France Inter radio on Tuesday.

“We say that there can be a few hundred centrifuges, but the Iranians want thousands so we’re not in the same framework.”

Paris has long held out for strict terms in the negotiations and it was not immediately clear whether Fabius was spelling out Paris’ position or that of the six powers, also including the United States, Germany, Britain, China and Russia.

Western officials say Iran wants to maintain a uranium enrichment capability far beyond what it currently needs for civilian purposes. Iran says it wants to avoid reliance on foreign suppliers of fuel for planned nuclear reactors.

U.S. and Iranian officials held talks in Geneva on Monday to tackle ways of breaking a deadlock which has raised the likelihood that the deadline will lapse without a deal meant to head off the risk of a Middle East war over the nuclear issue.

The negotiations ran into difficulty last month with each side accusing the other of making unrealistic demands, raising doubts about prospects for a breakthrough next month.

“We are at a critical juncture in the talks,” U.S. State Department deputy spokeswoman Marie Harf told reporters in Washington, as part of consultations before the next round of Vienna negotiations scheduled for June 16-20.

“We think we’ve made progress during some rounds but as we said coming out of the last one we hadn’t seen enough made, we hadn’t seen enough realism,” she said.

A French diplomatic source said officials from France and Iran would meet on Wednesday to discuss the Vienna negotiations. And Russian officials will have talks with the Iranians in Rome on Wednesday and Thursday, according to Iranian media.

“There are still gaps … in order to bring our views closer, the other side must make tough decisions,” Araqchi said.

 

A second senior Iranian official, TakhtRavanchi, was quoted as saying that putting an end to sanctions was one of the issues discussed during the bilateral session with the Americans.