The man who served as David Cameron's director of strategy said the former prime minister thought Barack Obama was one of the "most narcissistic, self-absorbed people" with whom he had ever dealt.
Steve Hilton, who was once one of Cameron's most senior advisers, now hosts a TV show on the American network Fox News.
In the most recent episode, he defended President Donald Trump against allegations made in a new book that he was mentally unfit for office by railing against previous presidents and their failings.
He claimed Obama's high-handed manner was in part responsible for disasters such as the rise of the Isil.
His words cast a new light on the so-called bromance between Cameron and Obama.
"As for Obama, all I can tell you is my old boss, former British prime minister David Cameron, thought Obama was one of the most narcissistic, self-absorbed people he'd ever dealt with," he said during Sunday's episode of the Next Revolution.