Iranian Supreme Leader Ayatollah Ali Khamenei. (Supreme Leader Official Website / Handout/EPA)

Iran enters the endgame of the nuclear talks with what amount to two negotiating positions — the parameters reportedly endorsed in April in Lausanne, Switzerland, by Foreign Minister Mohammad Javad Zarif, and another set of “red lines” drawn this week by Supreme Leader Ayatollah Ali Khamenei.

The two positions are significantly different. The first version offers a workable basis for agreement. The second is fatally flawed. It’s not the first time that a country has sent two messages, public and private, on a sensitive issue. That’s how President John F. Kennedy resolved the Cuban missile crisis. But it’s discomforting less than a week before the deadline.

Secretary of State John Kerry travels to the final round of talks in Vienna assuming that the decisive final version will be what’s agreed to by Zarif at the bargaining table, not what’s said in an inflammatory speech by Khamenei. Past negotiating experience with Iran gives some reason for such hope: The Iranians have indeed made concessions they initially said were unthinkable; the very fact they’re negotiating with the one-time “Great Satan” shows that Khamenei is pliable.

“We and Iran both know what’s needed for a deal,” a senior administration official said Thursday. “We have to get the Lausanne parameters or we will not have a deal. We all understand that; all parties understand that.”

But get it in writing. The United States won’t be sure which language prevails until a written agreement is endorsed by the Iranian parliament. The Iranians could make the same argument about the U.S. Congress. That’s why this process will remain murky for weeks, even if the parties agree on a “text.”

What the United States can’t do is accede to Khamenei’s red lines. They contradict several key items in the package tentatively reached April 2, involving the inspection of military facilities and the timing of the lifting of sanctions. No deal would be a better outcome than the severely weakened framework demanded by Khamenei.

Ambiguity and face-saving are part of any successful negotiation, to be sure. And dueling texts were part of the Lausanne resolution. Zarif publicly supported a “joint statement” that was vague on details. Kerry separately issued a fact sheet, with the detailed parameters that U.S. officials said had been agreed to privately. But it wasn’t a signed deal.

Khamenei himself straddled. “I am neither for [the framework] nor against it,” he said April 9. He warned on May 20 that “Iran will not give access to its scientists” as demanded by the International Atomic Energy Agency (IAEA), and that Iran would not yield to “bullying demands.”

Khamenei set his parameters in a speech on Tuesday. The “inspection of our military sites is out of the question,” he insisted, where Zarif had told me April 29 onstage at New York University that such investigation of “undeclared facilities” was encompassed by Iran’s acceptance of the IAEA’s “additional protocol.” Khamenei also rejected IAEA verification of its compliance, contradicting Zarif’s declaration in Lausanne that sanctions would be lifted “simultaneously with the IAEA-verified implementation by Iran of its key nuclear commitments.”

Was Khamenei playing a political game — talking tough even as Zarif prepared to ratify concessions? That’s what some U.S. experts are hoping. But they should read the fine print at the bottom of Khamenei’s statement. Any “propaganda” suggesting that “some red lines [announced by the supreme leader] are agreed in private meetings to be crossed is totally wrong and a lie,” it said.

Discussing the dilemma of negotiating with Tehran, former secretary of state Henry Kissinger famously remarked that Iran had to decide whether it wanted to be a nation or a cause — a member of a rules-based global order or a revolutionary outlier. As the nuclear negotiations near a climax, Iran seems to want to be both. This Janus-like approach won’t work much longer. It will generate suspicion rather than confidence. Now is the time for clarity, not ambiguity.

Russia, China and other major powers have joined the United States in demanding that Iran accept verifiable limits to ensure that its nuclear program is civilian-only. Khamenei has fuzzed this commitment at the very moment it needs to become sharper. Perhaps that’s a last-minute Iranian bargaining tactic; if so, it’s a foolish one.

But let’s assume that Khamenei is serious. He truly doesn’t want an agreement that will bind Iran’s nuclear program for at least 10 years. If so, the right answer is: Come back when you’re ready to make a serious deal.

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