this tension has been drawing for some time. hasn't it? >> reporter: you know, john, yes it has. for whatever reason the president has taken an instant dislike to the mayor. he's the first muslim mayor of london. he's a labor party mayor. not the government party and you know, sadiq khan you know fired back. i think it was mostly based from sadiq khan in the beginning to a great exception with the president's muslim ban. that really ticked off a lot of the world. that spat has been going on for a long time so really nothing new, the spat. and again, these verbal fisticuffs over twitter were dispensed with. once the president landed, there has been no more of that. >> just to finish up on the royal visit, because there will be those in the united states who may not follow the royals so closely who will ask, given the tension between donald trump and some government officials in the uk, given his insertion of himself into the whole brexit debate, why then would the queen bend over backwards to provide