Theresa May to tell Gulf leaders Iran nuclear deal is 'vitally important'

British PM will underline value of deal in first intervention since election of Donald Trump, who wants to tear up agreementTheresa May will say the Iran nuclear deal is “vitally important” in her first major intervention on the issue since the election of Donald Trump, who has said he plans to tear up the agreement secured by the Obama administration.Speaking on Wednesday, the prime minister will tell Gulf leaders in Bahrain that Iran remains a threat to the stability of the Middle