The senior US intelligence official on Tuesday stressed that a recent report on Iran had concluded that Tehran had halted only one part of its alleged nuclear weapons programme.

Admiral Michael McConnell, director of national intelligence, said the November national intelligence estimate had concluded that Tehran had ceased only efforts to covertly enrich uranium and design nuclear warheads. “The only thing that they’ve halted was nuclear weapons design, which is probably the least significant part of the programme,” he told the Senate intelligence committee.