Here is an extract of what David Cameron will sing in welcome to President Obama on his arrival:
"Oh! Mr. President, what shall I do?
I want to go to Panama, but I'm stuck in an EU!
Take me back to Chelsea because I'm in a jam,
Oh! Mr. President, what a silly boy I am!"
Apologies, and there can't be enough of them, to Marie Lloyd and George and Thomas Le Brunn in borrowing from "Oh, Mr. Porter".
Wikipedia says that the song was alluded to in the book "Ulysses" by James Joyce, I suppose that makes more sense than Cameron.