US President Donald Trump and US First Lady Melania Trump arrive by helicopter at Windsor Castle in Windsor, west of London, on July 13, 2018 for an engagement with Britain's Queen Elizabeth II on the second day of Trump's UK visit. US President Donald Trump launched an extraordinary attack on Prime Minister Theresa May's Brexit strategy, plunging the transatlantic "special relationship" to a new low as they prepared to meet Friday on the second day of his tumultuous trip to Britain. / AFP PHOTO / POOL / Ben STANSALL