he's been a friend of mine. he's very nice. i have a very good relationship with him. i have a very good relationship with nigel farage, with many people over there. we'll see what happens. >> president trump getting into a spat with london mayor sadiq khan after khan put out an op-ed calling the president a global threat. mr. trump compared him to the mayor of new york. >> i don't think much of him. i think that he's the twin of de blasio, except shorter. >> before landing, president trump sent out a pair of tweets attacking khan, insulting his height among other things. let's go live to london and bring in cnn's clarissa ward. the timing interesting for president trump, amid an ongoing difficulty in the brexit negotiations and potentially a new prime minister coming soon. >> that's right, and i think that's exactly why here in the uk everyone is essentially girding themselves to see what