Over the weekend, Khan wrote an op-ed in The Guardian marking 80 years since Nazi Germany invaded Poland, in which he claimed that the global rise of “extremist far-right movements and political parties” are “fuelled by Donald Trump, the global poster-boy for white nationalism.”

In a subsequent interview with Politico, Khan mocked Trump for “dealing with a hurricane out on the golf course.” The comment followed Trump’s decision not to attend the World War II commemoration in Poland purportedly to stay in the U.S. to concentrate on Hurricane Dorian, but then reportedly proceeded to play golf at his club in Virginia instead.

Khan then doubled down on the accusations he had made in his op-ed, telling Politico that Trump “amplifies racist tweets; amplifies the tweets of fascists; says things that are deeply objectionable. If I don’t stand up and call that out I think I’m doing a disservice to Londoners who chose me as their mayor.”

Trump didn’t take kindly to the accusations and took to Twitter Tuesday morning to defend his golf playing. Calling Khan “the incompetent Myaor of London,” Trump claimed that he had played a “very fast round of golf.” 

“Many Pols exercise for hours, or travel for weeks,” he added. “Me, I run through one of my courses (very inexpensive).” 

After going on to say that Obama “would fly to Hawaii” during his presidency, Trump wrote that the London mayor should “focus on ‘knife crime,’ which is totally out of control in London. People are afraid to even walk the streets. He is a terrible mayor who should stay out of our business!”

This is far from the first time the U.S. President and London Mayor have traded barbs. Prior to his own election as president, Trump accused Khan of making “rude” and “nasty” comments. And earlier this summer, Trump called Khan a “stone cold loser” after Khan wrote another op-ed that had appeared in The Guardian arguing that it was “un-British to roll out the red carpet for Donald Trump” prior to the President’s first official state visit to the U.K.

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