U.S. President Donald Trump leaves on Monday for a NATO summit in London and he is under pressure from British Prime Minister Boris Johnson to resist the temptation to wade into the British election campaign coming up later in December.
As a presidential candidate in 2016 and then as president since early 2017, Trump has shown no restraint in showing support for Britain's exit from the European Union and critiquing the politicians involved in the country's long-running Brexit debate.
But with Johnson leading polls as he faces Dec. 12 elections, the prime minister who is hosting the London NATO summit wants Trump to mind the guardrails, putting Trump in the unusual position of trying to avoid his normal impulse to comment on whatever he wishes.