Sadiq Khan, the mayor of London, rebuked the United Kingdom’s efforts to welcome President Donald Trump for his three-day state visit to the European nation that begins Monday.

In an 841-word opinion piece published by The Guardian on Saturday, Khan condemns Trump for starting an immigration policy that separated children from parents, using racism and xenophobia as election tactics and introducing a travel ban on predominantly-Muslim countries.

“No, these are not the actions of European dictators of the 1930s and 40s. Nor the military juntas of the 1970s and 80s. I’m not talking about Vladimir Putin or Kim Jong-un. These are the actions of the leader of our closest ally, the President of the United States of America,” Khan writes.

Khan, the first Muslim to be elected London’s mayor, and a member of Britain’s Labour Party, warns readers of an expanding allegiance to far-right politics, and classifies Trump as “one of the most egregious examples of a growing global threat.”

Khan and..