Seven-natio talks on a deal meant to start a rollback of Iran’s nuclear program in exchange for sanctions relief were delayed Thursday as senior envoys from both sides wrestled with a draft they hoped would be acceptable to both Tehran and its six world powers negotiating with it.

Deputy Foreign Minister Abbas Araghchi suggested that the momentum characterizing much of a previous round had been slowed, as top EU diplomat Catherine Ashton sat down with Iranian Foreign Minister Mohammad Javad Zarif to discuss the draft.

As the two broke for lunch, Zarif said the two were discussing “details and wording” of the document but pointed to what his country sees as a potential problem ahead.

“We expect the West to have a united stance over draft,” he told Iranian state TV, alluding to what Iran says were complications to reaching a first-step deal at the last round earlier this month because of differences among the six world powers.

Araghchi suggested those differences had set back the talks, telling The Associated Press: “What we are trying now is to rebuild confidence that we lost in the previous round of negotiations.” He spoke of some unspecified “misunderstanding or … mismanagement in the previous round,” and of the “difficult job” of trying to bridge differences.

He also said talks have included possible ways to reduce sanctions on Iranian oil sales and banking. The U.S. and its partners have spoken of offering some financial concessions, such as unfreezing Iranian bank accounts from previous oil sales.

If the talks produce a deal to freeze Iran’s nuclear efforts, negotiators will pursue a more comprehensive agreement that would ensure that Tehran’s program is solely for civilian purposes. Iran would get some sanctions relief under such a first-step deal, without any easing of the harshest measures — those crippling its ability to sell oil, its main revenue maker.

Details of sanctions relief being discussed have not been revealed. But a member of the U.S. Congress and legislative aides on Wednesday put the figure at $6 billion to $10 billion, based on what they said were estimates from the U.S. administration.

The aides and the member of Congress demanded anonymity because they weren’t authorized to divulge the estimate publicly.

A member of the Iranian delegation said his country recognizes that core oil and banking sanctions could not be lifted immediately but suggested Iran was looking for some relief in those sectors over the six-month time-frame of a first-step agreement.

He also indicated that Iran was ready to discuss a limit on its uranium enrichment — which can create both reactor fuel and the core of nuclear warheads. But he suggested that Iran wants at least indirect mention of Tehran’s insistence that it has a right to uranium enrichment — something the United States and its allies have resisted.

Iran has suggested it could curb its highest-known level of enrichment — at 20 percent — in a possible deal that could ease the U.S.-led economic sanctions.

But Iranian leaders have made clear that their country will not consider giving up its ability to make nuclear fuel — the centerpiece of the talks since the same process used to make reactor stock can be used to make weapons-grade material.

Warnings from Iran’s supreme leader that his country’s readiness for compromise has its limits added to the sense of some work ahead. The tough talk reflected the tensions from nearly a decade of negotiations that have begun to make headway only recently.

Ayatollah Ali Khamenei, Iran’s top lead leader, voiced support for the talks Wednesday but insisted there are limits to what Tehran will deal away at the negotiating table. He blasted Israel as “the rabid dog of the region” — comments rejected by French President Francois Hollande as “unacceptable.”

Israeli Prime Minister Benjamin Netanyahu, in Moscow to meet with President Vladimir Putin, renewed his demand for a full stop to all Iranian nuclear programs that could be turned from peaceful uses to making weapons.

Israel wants a settlement that is “genuine and real,” he said.

“Israel believes that the international community must unequivocally ensure the fulfillment of the U.N. Security Council’s decisions so that uranium enrichment ends, centrifuges are dismantled, enriched material is taken out of Iran and the reactor in Arak is dismantled,” Netanyahu said, referring to Iran’s plutonium reactor under construction.

He urged the world to see the “real Iran.” That, he said was not a YouTube message from Zarif saying Iran wanted peace, but Khamenei calling Jews “‘rabid dogs.'”

“They must not have nuclear weapons,” he told a gathering of Russian Jews. “And I promise you that they will not have nuclear weapons.”

(AP)