ELLESBOROUGH, England—Tensions were running high ahead of planned talks between President Donald Trump and U.K. Prime Minister Theresa May, after the U.S. leader in an interview bashed the prime minister’s approach to Brexit and threatened that her plan would “kill” the chances of a trade deal.
Mr. Trump on Friday morning arrived at the Royal Military Academy Sandhurst in southern England, where he and Mrs. May viewed a military demonstration by U.S. and U.K. forces. Their first interaction after the publication of the interview...