Iran’s decision to halt the implementation of key commitments to its 2015 nuclear deal has plunged the Middle East into dangerous unpredictability.

Tehran will draw criticism for its move. But Donald Trump bears much of the responsibility. It was the US president who last year unilaterally withdrew from an international accord that had taken years of difficult negotiations to seal. In one action, Mr Trump undermined the international order and put the Iran nuclear deal on life-support.

Iran continued complying with the agreement as it enjoyed the political backing of the other main signatories: Germany, France, the UK, Russia and China. But renewed US sanctions have triggered the collapse of the Iranian economy as the regime’s oil exports have plummeted and foreign investors fled out of fear of falling foul of Washington’s punitive measures.