Former US deputy secretary of state William Burns said Tehran's nuclear know-how cannot be destroyed by military action, emphasizing a strong negotiated agreement is the best of the available alternatives on Iran's nuclear issue.
The veteran diplomat, who has played a key role in nuclear talks with Iran on a final settlement to the long-running dispute over Tehran's nuclear work, made the remarks in a recent interview with Politico.
"I understand the argument for no enrichment capacity at all. In a perfect world, you wouldn't have any domestic enrichment program, and the United States has argued in lots of other circumstances that people ought not to do domestic enrichment, because it's not commercially sensible," he said.
He added, "The reality is that the Iranians have developed over the course of the last decade or more the know-how to enrich, they know their way around basic enrichment technology, and you can't wish that away, you can't dismantle it away, you can't bomb it away.
"And so the reality is that if you want to get a negotiated agreement, the question is how to constrain it, verify it over a long duration, so that you have strong confidence that they're not going to break out and try to develop a weapon."
Iran denies the allegation that it may be seeking to develop the capability to build nuclear weapons under the guise of a civilian program, saying the work is meant only for peaceful applications such as electricity generation and medical research.
On the opposition to a nuclear deal voiced by Israeli Prime Minister Benjamin Netanyahu and some US lawmakers, Burns said, "Certainly if an agreement is reached, I'm sure the administration will work very closely with Congress to make its case. But there's a lot of ground that has to be covered between here and actually getting to an agreement."
In addition, he said, "The other thing, too, is to keep a sense of perspective. Even when you think back to the end of 2013, and we finished the interim agreement, there was huge criticism at the time, including from Prime Minister Netanyahu, that this was the deal of the century for the Iranians.
"The reality is that turned out to be a pretty solid agreement. It froze and rolled back in some significant ways the Iranian program; it gave us intrusive verification measures we didn't have before which provided a good foundation on which to build some of those measures for a comprehensive agreement."
