Iran’s supreme leader, Ayatollah Ali Khamenei, addresses Iranian officials beneath a portrait of the late Ayatollah Ruhollah Khomeini in a mosque at his residence in Tehran. (Office of the Iranian Supreme Leader/Via AP)

Just days before Secretary of State John F. Kerry heads to Vienna to join nuclear talks with Iran, the country’s supreme leader is staking out what he considers the “major red lines,” any one of which could sink a deal.

In a speech Tuesday night, Ayatollah Ali Khamenei laid out several demands, including the lifting of economic sanctions as soon as a deal is reached and before Iran dismantles some of its nuclear infrastructure. He also ruled out a freeze on nuclear research and development, inspections of military sites and restrictions lasting 10 years or more.

“We don’t accept 10-year restriction,” he said. “We have told the negotiating team how many specific years of restrictions are acceptable. Research and development must continue during the years of restrictions.”

The United States is leading a negotiating group that includes the four other permanent members of U.N. Security Council, plus Germany. Despite the hostility between the United States and Iran, direct and intense talks between the two nations have made up the backbone of the negotiations.

On Wednesday, Khamenei tweeted what he called the seven “major red lines” in the talks. As Iran’s supreme leader, he has the final say in all matters of state.

But the limitations he outlined could undercut the ability of Iranian negotiators to make concessions as a June 30 deadline for a final deal looms. They also appear to contradict U.S. positions in an April 2 framework agreement, and American negotiators say they will not back down from them.

For example, Khamenei reiterated that all economic, financial and banking sanctions must be lifted on the same day that a deal is signed. He said that includes not only sanctions imposed by the United Nations, but also those voted into law by Congress.

“Lifting sanctions can’t depend on implementation of Iran’s obligations,” he said.

The Obama administration has said that the sanctions will be phased out, but only after inspectors from the International Atomic Energy Agency verify Iran’s compliance on dismantling centrifuges used to enrich uranium and the country reduces its stockpiles of the material and converts its enrichment plants into labs. Enriched uranium can be used as fuel for nuclear power plants and, at much higher concentrations, as fissile material for nuclear weapons.

Iran has insisted that its nuclear program is for peaceful purposes, such as producing energy and medical isotopes, and that it has no intention of building nuclear weapons, which Khamenei says are forbidden by Islam. However, many observers are skeptical of Iran’s assertions.

Khamenei also took a swipe at the IAEA, whose work would underpin any agreement.

“Because the IAEA has proved for several times that neither does it work independently, nor is [it] fair, and thus we are pessimistic about it,” according to his tweet. Khamenei said the red lines he outlined in the tweet were all points he had made in meetings with officials on Tuesday.

Some believe his remarks amount to a last stab at driving a hard bargain.

“It’s unlikely that Khamenei would have allowed his negotiators to come this far only to sabotage the deal at the last moment,” said Karim Sadjadpour, an Iran analyst with the Carnegie Endowment for International Peace. “He doesn’t want to be held responsible if talks fail. He appears overconfident that the other side won’t take no for an answer. It’s natural to try and extract more concessions.”

The talks between Iran and the six world powers have been going on for more than a decade, but they gained momentum a year and a half ago after the election of President Hassan Rouhani, who pledged to free Iran from the burden of international sanctions. The negotiations aim to provide sanctions relief if Iran agrees to curb its nuclear program. Hard-liners in Iran oppose any deal with the United States or one that would compromise a nuclear program that is a symbol of national pride.

Kerry will join the talks this week for the first time since he was sidelined when he broke a leg in a bicycle accident on May 31, a day after meeting with Iranian Foreign Minister Mohammad Javad Zarif in Geneva.

Although U.S. negotiators insist they are aiming for a final deal by June 30, Iran and several of the European countries negotiating alongside the United States have urged an extension. In practical terms, the Obama administration would like to present a final deal to Congress by July 10. Under legislation enacted in May, Congress would have 30 days to review the deal if the July 10 deadline is met. If a final deal is presented after that date, Congress would have 60 days to review it.

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