BRUSSELS European Union officials said on Monday that Iran has agreed to discuss a proposal from six world powers to curb its production of high-grade uranium at a meeting in Moscow next week in an apparent de-escalation of tensions ahead of the talks.
The development follows more than two weeks of wrangling between Iranian diplomats and Western negotiators over preparations for the closely-watched round of nuclear talks which had cast some doubts over what can be achieved in Moscow.
A tense exchange of letters between EU diplomats, who deal with Iran on behalf of the six powers, and Iranian officials had earlier appeared to suggest Tehran may be backtracking on its expressed willingness to discuss their most pressing concern - high-grade uranium enrichment even in broad terms.
But on Monday, Iran's chief nuclear negotiator Saeed Jalili agreed to focus on the six powers' demands at the Moscow meeting, during a one-hour phone conversation with EU foreign policy chief Catherine Ashton.
"The Iranians agreed on the need for Iran to engage on the (six powers') proposals, which address its concerns on the exclusively peaceful nature of the Iranian nuclear program," a spokesman for Ashton said.
Ashton heads talks with Iran on behalf of the six powers: United States, China, Russia, Germany, France and Britain.
The group, known as P5+1, because it consists of the five permanent members of the U.N. Security Council plus Germany, aims to persuade Iran to curb its nuclear work, because of suspicions it aims to produce weapons. Iran denies that.
In the immediate term, they want Tehran to stop enriching uranium to 20 percent fissile purity, because production of such material represents a major technological advance en route to making weapons-grade material.
They put forth a proposal on how to achieve this at a round of talks in Baghdad in May, in which Tehran would stop production, close an underground facility where such work is done and ship any stockpile out of the country.
In return, they offered to supply it with fuel for a reactor in Tehran, which requires 20-percent uranium, and to ease sanctions against the sale of parts for commercial aircraft to Iran.
No agreement was reached in Baghdad but the seven countries agreed to continue discussions on June 18 and 19 in Moscow.
Tensions flared up soon after the meeting in the Iraqi capital, when Iranian officials asked for preparatory meetings with experts. P5+1 negotiators were reluctant to agree without explicit agreement from Tehran that high-grade uranium would be discussed, diplomats said.
Tehran, in response, had accused the powers of failing to honor agreements reached in previous negotiations and trying to scupper talks.
But a diplomat with knowledge of the issue said that Iran was no longer demanding an experts' meeting.
"They are prepared to go to Moscow and address our proposals," the diplomat said, speaking on condition of anonymity.
(Reporting by Justyna Pawlak and John O'Donnell; Editing by Jon Hemming)