By Lesley Wroughton and Parisa Hafezi
LAUSANNE, Switzerland (Reuters) – The United States and Iran inched closer to a political deal that would set the stage for a landmark nuclear agreement but differences between Tehran and six major powers remain vast with no sign of an imminent breakthrough, officials said on Monday.
U.S. Secretary of State John Kerry and Iranian counterpart Mohammad Javad Zarif held four hours of nuclear talks in the Swiss city of Lausanne before the Iranian delegation headed to Brussels for meetings with European ministers.
"We're obviously in crunch time right now, and the next couple of days leading up to this weekend will be key," State Department spokeswoman Jen Psaki told CNN from Washington. But she played down expectations that a political agreement would be clinched this week.
"We fully expect we will take to the end of the month to determine if we can get to an agreement that both sides can live by," she said.
With the Iranian new year holiday of Norouz approaching this weekend, officials close to the talks say it will be difficult to complete a political agreement this week. If it is not possible by the weekend, the talks could reconvene in the last week of March.
Zarif said all sides needed to keep talking this week to see what could be achieved.
"On some issues we are closer to a solution and based on this we can say solutions are within reach. At the same time, we are apart on some issues," he told the Iranian news agency IRNA.
Six world powers — the United States, Germany, France, Britain, Russia and China — are trying to reach a political framework agreement with Iran by the end of the month that would curb Tehran’s most sensitive nuclear activities for at least 10 years in exchange for the gradual easing of some sanctions.
The parties have set a June 30 deadline to finalize all the technical details of an accord. Western officials say privately that overcoming disagreements on some of the remaining sticking points would be very difficult.
The meeting between Kerry and Zarif included U.S. Secretary of Energy Ernest Moniz and Iran's nuclear chief Ali Akbar Salehi, who also met on Sunday to negotiate technical details of Iran's nuclear program.
"I'm very optimistic," Salehi told reporters afterwards, leaving Zarif and Kerry in the room for a one-on-one meeting.
Kerry has urged Iran to make concessions that would allow the six powers to reach a political framework agreement for a nuclear deal that would lift sanctions in exchange for tight restrictions on Tehran's nuclear program and increased monitoring of its atomic sites.
The West suspects Tehran of ambitions to create an atomic weapons capability. Tehran denies that and says its research is for purely peaceful purposes.
In Brussels, British Foreign Secretary Philip Hammond also said a framework agreement was still some way off.
"There are areas where we've made progress, areas where we have yet to make any progress," he told reporters.
PROGRESS MADE IN TALKS BUT OBSTACLES REMAIN
After their meeting in Brussels, the Iranian delegation will return to Lausanne for more talks with the Americans, and will be joined later in the week by European ministers.
In Tehran, former nuclear negotiator and current parliament speaker Ali Larijani said failure to get an agreement would not be a tragedy.
"If we don’t reach a comprehensive agreement, the world will not end," he said in a news conference broadcast on state television. "Right now we are without a comprehensive agreement and we are living our lives. Meanwhile, if an agreement doesn’t take shape, we will go after a different solution."
The sides have twice extended the talks on a long-term accord that the United States says must have a duration of at least 10 years. They signed an interim deal in November 2013 that gave Iran limited sanctions relief in exchange for some limitations on sensitive nuclear work.
After months of deadlock, there have been areas of progress in the talks recently, Iranian, U.S. and European officials say. The number of enrichment centrifuges Iran wants to operate over the long term, one of the biggest sticking points in the talks from the beginning, is likely resolvable if Tehran can keep around 6,500 of the machines that purify uranium, they say.
There are also discussions about the size of Iran's uranium stockpiles and how much would be relocated to Russia or another country, Western officials say. Originally, Iran wanted to enrich 2.5 tonnes of uranium per year, but could settle at half a ton, a senior Iranian official said. The remainder would be turned into fuel rods or sent to Russia, he added.
Recently the United States and France agreed to consider the possibility of a swift suspension of U.N. nuclear sanctions at the outset of any deal, in addition to freezing some of the most painful U.S. and European energy and financial sanctions.
The subject of lifting U.N. sanctions has turned into a sensitive one in the United States, where Republicans in Congress opposed to engaging Iran accuse President Barack Obama of seeking to bring an agreed deal to the U.N. Security Council first in an attempt to bypass U.S. legislators.
Difficult issues remain, officials say, including Iran's insistence on pursuing advanced centrifuge research, Tehran's need to answer questions on past nuclear activities that could be arms-related, and the speed of lifting sanctions. Iran wants all sanctions lifted immediately but Western powers want a gradual easing of sanctions.
There is also a risk of nuclear proliferation. Prince Turki al-Faisal of Saudi Arabia said his country would seek the same terms granted to Iran in the event of a deal.
(Additional reporting by Louis Charbonneau in Lausanne and Sam Wilkin in Dubai; Writing by Louis Charbonneau and Parisa Hafezi; Editing by Ralph Boulton and Giles Elgood)