Iran threatened today to accelerate its nuclear programme in violation of a 2015 nuclear agreement and to move closer to building an atomic weapon — something US President Donald Trump has vowed to prevent.

But it was Trump who withdrew the US from the Obama-era nuclear agreement in May 2018, saying the deal wasn't tough enough.

Since then the Administration has steadily imposed ever harsher sanctions on Iran as the country's economy has sharply declined.

Until recently, Iran has held up its side of the bargain, which is still in force with five other countries: freezing much of its nuclear