As Iran and Western powers winded down nuclear talks on Thursday, having arrived at a framework agreement for future negotiations — but with little concrete progress — a Western diplomat revealed that European Union foreign policy chief Catherine Ashton would be traveling to Iran in March to lead negotiations there.

The diplomat, who said Ashton would visit Tehran March 9-10, demanded anonymity because his information was confidential.

In a joint statement at the end of the three-day talks, officials for both sides said they would meet again in Vienna on March 17, continuing a process likely to take at least six months and probably longer.

Expectations had been modest as the talks started Tuesday. The announcement of an agreement on future talks appeared aimed in part to raise hopes that the negotiations had a chance to succeed.

Iranian Foreign Minister Mohammad Javad Zarif, who came to the talks vowing that Iran would never strip down its nuclear facilities, was smiling and relaxed as he read out the joint statement.

But in a message apparently intended for skeptics at home who fear that Iran will give up too much, he told state TV afterward that his nation would “not close down any site.”

The six on the other side of the table — the United States, Russia, China, Britain, France and Germany — want Tehran to agree to significant cuts in its nuclear program.

Iran opposes cuts, saying its program is not aimed at building weapons. The United States and its partners say Iran must accept an agreement if it wants an end to the sanctions crippling its economy.

“We have… identified all of the issues we need to address for a comprehensive and final agreement,” said Ashton, who convened the negotiations.

“It won’t be easy, but we’ve gotten off to a good start,” she said in a statement read later in Farsi by Zarif.

The talks are designed to build on a first-step deal that commits Iran to initial nuclear curbs in return for some easing of sanctions. The deal can be extended by mutual consent after six months.

Under terms of that accord, Iran has already begun to carry out a series of steps. These include diluting or converting its stockpile of higher enriched uranium and not to make any more for the next six months.

Iran also agreed not to increase its stockpile of lower-enriched uranium and not to set up new centrifuges at its enrichment plants, as well as to allow rigorous oversight by the UN nuclear agency.

Sanctions being suspended during this interim agreement include those on Iran’s petrochemical exports, its trade in gold and precious metals, its car industry and the supply of parts for Iran’s civil aviation industry. No new sanctions will be imposed while the first-step deal remains in effect.