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Talks on Iran's nuclear program are entering a crucial weekend. The deadline for reaching the broad outlines of a deal is Tuesday. The U.S. seeks to prevent Iran from building a nuclear weapon. The goal for Iran is relief from economic sanctions. NPR's Peter Kenyon is in Switzerland, where the talks are taking place, and he explains why lifting sanctions is tricky and contentious.
PETER KENYON, BYLINE: When Iran's leaders talk about sanctions, it's usually to declare them both illegal and ineffective. And yet getting sanctions lifted as quickly as possible remains Tehran's top priority.
(SOUNDBITE OF PERSIAN NEW YEAR CELEBRATION)
KENYON: During the recent Persian New Year celebration, Supreme Leader Ayatollah Ali Khamenei told a mosque gathering that a U.S. proposal to suspend certain sanctions and lift others only after Iran follows through on its nuclear commitments is not to be trusted.
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SUPREME LEADER AYATOLLAH ALI KHAMENEI: (Through interpreter) This is an American trick. They say, we make a deal, and then we monitor Iran's behavior and then lift the sanctions. It is not like that. The sanctions should be removed immediately after the agreement.
KENYON: U.S. and European officials say there's little doubt that a remarkable nexus of sanctions from the U.S., EU and U.N. Security Council played a big role in bringing Iran to the table.
The issue, now that Iran appears willing to make tangible concessions to prove it's not seeking a nuclear weapon, is how to provide sanctions relief without totally giving up the leverage they provide. It's clear that if there is to be a final deal, Iran will need some early sanctions relief to quiet hard-line critics back home. There are plenty of frozen Iranian assets that could be released, but that's not lifting sanctions, which is what Iran's leaders have promised their people. This may be where the U.N. sanctions come in. With all five permanent members of the Security Council at the table with Iran, there's little to stop the council from simply passing a new resolution that either suspends or cancels some of the sanctions.
The U.N. sanctions aren't that important economically but they may be important to Iran's sense of national pride. Analyst Jim Walsh with the Security Studies Program at MIT says Tehran was stung by these sanctions, coming as it were, from the entire international community.
JIM WALSH: Certainly the lifting of U.N. sanctions would carry a bigger punch. It would be something tangible - not in effect, but in principle - that the Iranian public could recognize and for which Rouhani and his administration would get credit.
KENYON: There are pitfalls for both sides. U.S. officials worry that once lifted U.N. sanctions could be hard to replace since Russia or China could veto them. They're seeking a suspension, preferably with a mechanism to restore sanctions, if Iran doesn't comply with a nuclear deal. Meanwhile, Iran would want some U.N. action to ensure that the U.S. and its allies live up to their end of any bargain.
When it comes to the American sanctions, some were imposed by President Obama, and those he can suspend or left. Even some congressional sanctions could be waived by the president. Lifting others, however, would require a congressional vote. The toughest sanctions are the ones keeping Iran out of the global banking system. Analyst Jim Walsh says if those were lifted and Iran then violated the agreement, they could probably be reimposed because most countries tend to abide by them to stay in the banking system.
WALSH: In some ways, the U.S. always has this in their back pocket. The European banks and Chinese banks aren't going to want to risk falling out of favor with the international banking system, even if they want to do business with Iran.
KENYON: Sanctions may have attracted Iran to the table, but they could also drive it away. President Obama has warned that if Congress imposes new sanctions, the talks could be derailed. Peter Kenyon, NPR News, Lausanne, Switzerland. Transcript provided by NPR, Copyright NPR.