ARUN RATH, HOST:
Domestic politics in the U.S., Iran and Israel seem to have muddied the waters in the Iranian nuclear negotiations. Even so, there's a growing anticipation that the U.S. and Iran are close to reaching an agreement to restrict Iran's nuclear program. Secretary of State John Kerry is in Lausanne, Switzerland, tonight for more talks with Iran's foreign minister. It's their first meeting since a controversial letter Republicans on Capitol Hill warned that a deal wouldn't be finding and might not last beyond President Obama's term in office. NPR's Peter Kenyon joins us now from Lausanne. Hi, Peter.
PETER KENYON, BYLINE: Hi, Arun.
RATH: So that letter from 47 Senate Republicans got a lot of attention in Tehran. Could that change the Iranians' position at the negotiating table?
KENYON: Well, that's one thing that negotiators hope to find out here. There was some speculation that seeing this discord in Washington might tempt Iran to seek a better deal. But, frankly, both sides already know about the pressures back home. Iranian lawmakers have their own deal-wrecking legislation in their back pocket, for instance, that they've threatened to enact. The focus here, at the moment, still seems to be on finding out whether they can reach this framework accord on the major points in the very near future and, hopefully, a final deal a few months after that.
RATH: So where do the two sides seem to be making progress?
KENYON: One area is a big one, and that's enrichment - Iran's ability to produce its own nuclear fuel, which can power an energy reactor or, at a much higher level of purity, a nuclear warhead. It looks like Iran may be willing to stop several thousand centrifuges from enriching uranium, although it would still have thousands more than Washington and its allies were originally willing to agree to.
Also - and importantly - Iran seems ready to ship most of the fuel of those centrifuges would produce out of the country. Now, a negotiator from a former team on Iran, Hossein Mousavian, recently confirmed what he called Iran's flexibility on this issue. This is a big concession on both sides, actually, sure to arouse the ire of hard-line critics. But if you don't get these kind of concessions, there's just not going to be a deal.
RATH: So if they're making - if they're getting closer on those issues, what are the remaining sticking points?
KENYON: Well, there are still a number of those. Sanctions is a very big one for Iran. It's demanding a quick lifting of the most painful ones. That seems unlikely. In that interview I just referred to, Mr. Mousavian, the former negotiator from Iran, seemed to concede that. He said there will be a period of confidence-building when Iran stays under extra nuclear restrictions and extra visits from UN inspectors. And, presumably, sanctions - at least some of them - will stay in place during that time.
And that leads to another pitfall, however - the duration of a deal. Once the confidence-building is over, after a decade - maybe a little longer - sanctions would come off. Critics say that leaves Tehran free to resume pursuit of nuclear weapons capability.
RATH: Peter, if the sides can't reach a framework agreement in the next couple of weeks, what does that mean for a final comprehensive accord?
KENYON: Well, in theory, it makes it easier to reach, but not a done deal. Putting hard numbers on some of these compromises and attaching definitions, writing up technical annexes - that's an enormous task. And the complaints from critics during this period would only increase.
RATH: And what about these claims that any deal won't be legally binding or won't last very long? Could all the diplomatic effort finally yield a deal that just isn't durable?
KENYON: This would be an executive agreement, not a treaty. That means Congress doesn't need to approve it. It also means a future president could, in theory, scrap it. That doesn't happen very often. But that really brings up the point that even if there's a deal in the coming months, nothing will actually be over.
I mean, this kind of an accord can only work if the commitments are lived up to by both sides under intense scrutiny, year after year, and the world sees that it's better off with this deal than without it. It could fall apart at any time for any number of reasons. There's a lot of scenarios for failure and only one for success - a lasting decision by Iran to stick with nuclear energy and forgo a nuclear weapon and a willingness by Iran's neighbors in the West to see it back in the global economy.
RATH: That's NPR's Peter Kenyon in Lausanne, Switzerland. Thanks, Peter.
KENYON: You're welcome, Arun. Transcript provided by NPR, Copyright NPR.