David Cameron reportedly put Barack Obama on hold in order to finish a tennis game, according to Rebekah Brooks' husband.
Charlie Brooks told the Racing Post Cameron kept the leader of the free world waiting because he thought he was about to finish him off in a third set.
"We're pretty good friends. I played tennis with him at Chequers one day," Brooks said.
"I won the first set easily, then he won the second set, and then someone came up to him and said 'Er... Mr Obama is on the phone for you, prime minister.' He said: 'I think we've got time for a third set - tell Mr Obama I'll ring him back.'"
Brooks added: "He obviously thought he had me on the ropes, and I beat him two sets to one."
No 10 said it was "baffled" by the claim and that there had been no calls from the president during the three weekends Brooks stayed at Chequers.
It added that calls between the president and the prime minister are scheduled by officials and set by an agenda.
The news comes just hours after Cameron won over a New York audience in an appearance on the Late Show with David Letterman.
The prime minister flew from New York to Brazil after the show to continued to "bang the drum" for British business on the back of the Olympics.