Boris Johnson is taking the helm with an urgent crisis brewing in the Gulf, where Iran’s seizure of a British oil tanker threatens to pull the UK and the international community into the escalating friction between Washington and Tehran. But in crisis there is opportunity, and the new prime minister should use his affinity with Donald Trump to de-escalate responsibly while reinforcing the battered transatlantic relationship around Iran.

Tehran has accused the tanker, the Stena Impero, of colliding with a fishing boat and violating international regulations. However, the seizure came shortly after Iranian leaders threatened to retaliate for the British seizure of an Iranian-flagged vessel in Gibraltar over suspicions that the ship had violated European Union sanctions on Syria.