TEHRAN, Iran — Iran is staking out a tough bargaining stance for the final phase of nuclear negotiations, with both its supreme leader and its moderate president saying Thursday that any deal must include an immediate lifting of withering sanctions.

While that might be popular domestically, it could be setting the bar too high for what negotiators will be able to deliver in the final deal they hope to reach by June 30.

Supreme Leader Ayatollah Ali Khamenei will have the final say on whether Iran agrees to a deal that could transform its relationship with the wider world -- and he is keeping everyone guessing.

In his first comments on last week's deal, Khamenei told a gathering of religious poets on Thursday that he "is neither for nor against" it. His reasoning was matter-of-fact: Because the agreement was only the framework of a final deal and not the accord itself, "nothing has been done yet," he said.

"What has happened so far neither guarantees a deal... nor does it guarantee the content of a deal," he said. "It doesn't even guarantee the talks will go on until the end and will lead to a deal."

Khamenei did say, however, that the punitive "sanctions should be lifted completely, on the very day of the deal" — something that has not been agreed upon.

He cautioned that the six world powers — the five permanent U.N. Security Council members and Germany — are "not to be trusted" and may try "to limit Iran" in further talks.

And he urged Iranian negotiators not to accept any "unconventional inspections" of Iran's nuclear facilities, stressing that the inspection of military facilities would not be permitted.

At the same time, however, he said a successful deal would show that negotiations are possible on other issues beyond the nuclear program.

Khamenei has backed the negotiating team despite criticism of the process from hard-liners. And this week, the negotiators won a major endorsement from the chief of Iran's Revolutionary Guard, Gen. Mohammad Ali Jafari, who praised their work "in defending the rights of the Iranian nation."

The supreme leader's caution seems designed to manage public expectations by characterizing the deal as just one more step on the road to an agreement whose outcome is far from certain.

But it also means the negotiations have his continued support.

"If you read between the lines, the supreme leader said he is willing to approve an extension of the talks," said Haleh Esfandiari, who directs the Middle East program at the Woodrow Wilson International Center for Scholars.

"If he was not interested in the negotiations, he would have just said 'we did what we could' and just stop," she said.

Iran's President Hassan Rouhani, a relative moderate, meanwhile aimed high during a ceremony Thursday marking Iran's nuclear technology day, which celebrates the country's atomic achievements.

"We will not sign any agreement unless all economic sanctions are totally lifted on the first day of the implementation of the deal," Rouhani said.

Iran and the six powers agreed last week on a framework deal that is meant to curb Tehran's nuclear activities while granting it quick access to bank accounts, oil markets and financial assets blocked by international sanctions.

But the deal does not include the immediate lifting of sanctions. Instead, it says sanctions put in place over Iran's nuclear program will be suspended once international monitors verify that Tehran is abiding by the limitations spelled out in the agreement.

"The process of sanctions suspension or relief will only begin after Iran has completed its major nuclear steps and the breakout time has been increased to at least a year," State Department spokesman Jeff Rathke told reporters in Washington on Thursday.

"That's consistent with what we said over the last week or so, and that was agreed upon by all the parties in Lausanne," the Swiss city where the framework agreement was reached.

The deal also specifies that if at any time Iran fails to fulfill its commitments, the sanctions would snap back into place.

Tehran-based analyst Saeed Leilaz downplayed the significance of Rouhani's remarks, which he described as "part of efforts by Iran to have the upper hand in the talks."

On the streets of Tehran, Iranians are hopeful a deal will be reached — and will change their lives for the better.

"I do not know politics and details. But I am sure (Foreign Minister Mohammad Javad) Zarif and his team will make it possible to have better relations with the West," said Maryam Hosseini, 35, who works in a beauty salon.

Mohammad Lak, a shopkeeper downtown, likened the back-and-forth of negotiations to a soccer match.

"Everybody is shouting, from spectators to players and the referee. But ultimately Iran will win the match and the West should agree to stop the sanctions," he said.

The West has long feared Iran's nuclear program could allow it to build an atomic bomb and that Tehran has used uranium enrichment — the key point of contention in the negotiations — to pursue nuclear weapons. Iran denies the charge, saying its nuclear program is for peaceful purposes only, such as power generation and cancer treatment.

Rouhani described the framework deal reached in Switzerland as evidence that Iran has "not surrendered to a policy of pressure, sanctions and bullying."

"This is our victory," he said.

Schreck reported from Dubai, United Arab Emirates.

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