Iran put the US on high alert when officials announced they would withdraw from key parts of the nuclear deal agreed in 2015 – meaning Tehran is moving ever closer to developing a nuclear weapon.
Monday saw the confirmation from Iranian officials that the nation had intentionally breached the limit on its stockpile of enriched uranium set by the Joint Comprehensive Plan of Action (JCPOA) agreed in 2015. Alongside US President Donald Trump’s withdrawal from the agreement last May, it sparked fears that Iran is getting serious about building a nuclear weapon. Technically, Iran could get their hands on one within months if an agreement isn’t reached with world powers – putting Washington on high alert.

The nuclear deal limited Iran to 300kg of low-enriched uranium – the level was set to 3.67 percent. This was reportedly enough for Tehran to use the material to fuel nuclear reactors and use the uranium for peaceful purposes.

Iran broke both of these conditions earlier this month, however, just over a year after Trump unilaterally pulled the US out of the deal.

To make one nuclear bomb, Iran would only need to possess 1050kg of low-enriched uranium to make the core, according to expert Joe Cirincione. It would then need to enrich it to 90 percent, which would whittle the stockpile down to 25kg.

On a technical level, much of the hard work has already been done, because more than half the effort needed to reach the 90 percent level is spent getting to a 4 percent enrichment level.

Once uranium is enriched to 20 percent – which Tehran has done previously – only a tenth of the work remains. Nuclear nonproliferation specialist Anne Harrington said: “It’s really hard at the start because you have very, very little of the uranium isotope you want.

“Natural uranium is almost all U-238 and initially getting that little bit of U-235 out is really difficult. “But the more refined you make it the faster the refinement process happens.”

Arms Control Association director Kelsey Davenport said that it would take less than a year for Iran to reach the so-called ‘breakout point’, where they have enough highly-enriched uranium to make a bomb.

It would then simply need to convert the uranium gas into metal, fit it with an explosive package and mount it on a ballistic missile.

The process could speed up if Iran frees up its 20,000 centrifuges – which are used to enrich uranium – but two-thirds are currently in storage under the nuclear deal.

Iranian scientists did extensive work on nuclear weapons at the turn of the century, but have curbed their research, according to the UN.

However quickly Iran can possess a nuclear weapon, there is still no consensus on their intention to do so. Experts such as Ms Davenport feel that Iran’s breach of the deal sent a warning to other nations, rather than signal a desire to build a nuclear bomb.

Iran has maintained that it will never build a nuclear weapon, with foreign minister Javad Zarif saying: “It is us who, because of our religious views, will never pursue a nuclear weapon.”