By Patrick Wintour Diplomatic editor
Leading Republican highlights potential challenges for UK foreign relations after Brexit
Boris Johnson risks jeopardising a free-trade deal with the US unless he pulls the UK out of the Iran nuclear deal, a leading Republican voice on Iran has said.
The warning by Richard Goldberg, until last week a member of the White House National Security Council (NSC), highlights the dilemmas UK foreign and defence policy-makers will face as Britain tries to steer its own course between Washington and Brussels after Brexit.
Source: UK-US trade deal under threat unless Iran stance changes, says Trump ally
