Iran nuclear concession would test big power unity

There is "no doubt " that Iran's policy would be to split the six, known as the P5+1, says Dennis Ross, until November a chief Middle East strategy adviser at the White House.

"I also have no doubt that they probably will put something on the table that they think will be attractive to some of the members of the P5+1," Ross told an audience at the Bipartisan Policy Center in Washington.

He said one such move could be Iranian assurances on a halt to stockpiling of 20 percent enriched uranium.

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