... The latest report from the International Atomic Energy Agency shows that Iran has a stockpile of 3,441 kilograms of enriched uranium, of which 122kg has reached a level of 60 per cent. Within four weeks, this could be initially enriched to 90 per cent, and then converted to uranium metal – sufficient to build two nuclear weapons. Given its existing stockpile, Iran could easily obtain more material should it decide to do so.
The second is the ability to design weapons. Iran had a structured nuclear weapons programme in place until 2003, and carried on with related work until 2009. Moreover, it has close military and economic ties with North Korea, which has successfully carried out six nuclear tests between 2006 and 2017. It is not improbable that Iran would be able to construct a nuclear weapon within a few weeks of obtaining sufficient enriched uranium metal – without the need for testing.
The greatest barrier is the third; the ability to deliver a weapon to its targets. Ballistic missiles, air and sea launched cruise missiles, and indeed gravity bombs are all possible options. But aircraft are relatively easily intercepted, and while Iran has an advanced missiles programme it does not yet appear to have systems capable of carrying nuclear warheads.
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