The world still has an opportunity to come to terms with Iran if the Tehran regime redefines its regional role and ends its interference in the affairs of its neighbours, according to Zalmay Khalilzad, US envoy to the United Nations.

Mr Khalilzad, speaking on the eve of the latest western diplomatic mission to Tehran at the weekend, said: “I think it’s possible to come to terms with an Iran that defines its objectives in a regional way and acts as a nation state, not as a revolution.”