Johnson also claimed the previous month that Barack Obama held a grudge against Britain because of his “half-Kenyan ancestry”.
“Would it not have been enough to say that you disagree with the American president’s point of view? Why discredit not just his motives, but even his persona, with borderline racist remarks?”
He went on: “The problem with hatred however is that, once used casually as an instrument in political discourse, it can prove very effective in reproducing itself. Of course this loss of control doesn’t happen when one is simply debating big topics with the chaps at the Oxford Union … But in the real world of a referendum on the future of your country the kind of arguments used have consequences.”
Elsewhere in Germany the reaction was negative. Simone Peter, the co-leader of the Green party, compared Johnson’s new job to “trusting the cat to keep the cream”.