Kim Darroch, the United Kingdom’s freshly resigned ambassador to the US, allegedly called US President Donald Trump’s withdrawal from the 2015 Iran nuclear accord an “act of diplomatic vandalism” and referred to the Trump Administration as “clumsy and inept.” The comments are said to have been in leaked diplomatic cables that led to Darroch’s resignation. Following general reports of the envoy’s criticism, President Trump called Darroch “a very stupid guy” and made clear that the White House would no longer deal with him. He also slammed Theresa May’s handling of Brexit, adding that “the good news for the wonderful United Kingdom is that they will soon have a new prime minister.” British authorities have reportedly opened an investigation into the leaked Darroch cables, which are believed to have originated from the British Embassy in Washington. The US and Britain differ on how best to contain Tehran’s atomic ambitions. European nations remain committed to salvaging the nuclear agreement by creating a complex financial mechanism that would allow for continued non-dollar trade with the Islamic Republic. The US-UK diplomatic spat comes as Iran has moved to surpass limitations on uranium enrichment stipulated in the pact; such enrichment is a precursor to the development of nuclear weapons. It also comes amid ongoing tensions in the Gulf, where Iranian military vessels recently attempted to “impede the passage” of a British oil tanker in the Strait of Hormuz – this after an Iranian ship was seized off the coast of Gibraltar over fears that Tehran was attempting to export oil to Syria in violation of international sanctions.