Commons speaker John Bercow was caught on camera yelling "we all love you Roger" as he watched Federer play at Wimbledon.
Mr Bercow enthusiastically cheered on the eight-time Wimbledon champion, as he stormed to victory in straight sets against Frenchman Lucas Pouille on Saturday.
The speaker even donned a blue t-shirt with Federer’s logo as he watched the game on Centre Court.
After the game, Federer spent time signing autographs on court.
John Bercow cheering Roger Federer at Wimbledon 2019 - In pictures
In a clip caught on the BBC, Mr Bercow can be seen yelling at the Swiss player: “We all love you Roger, all of us.”
However, Federer appeared not to notice the comments from Mr Bercow, sparking widespread amusement across social media.
James Davies posted the clip saying: “Speaker John Bercow there, getting ignored by Federer at #Wimbledon19.”
Another user wrote: “Hahaha is that John Bercow trying to get an autograph!”
Reshares of the video on Twitter also garnered tens of thousands of likes and hundreds of comments.
The speaker is reportedly a keen amateur tennis player himself, and an avid Federer fan.
Mr Bercow was pictured outside the Houses of Parliament with a tennis racket in 2013 after joining two million children for the Tennis Foundation and LTA schools tennis programme.
In 2014, he revealed how he had watched the grand slam champion play 65 times in that year alone.
He has also referenced Federer a number of times in the House of Commons during the lengthy Brexit proceedings.
In April this year, Mr Bercow took comfort in Federer’s Miami Open victory after another failed attempt to get Theresa May’s Brexit deal through the Commons.
He said: “Nothing is won tonight. In what do I take comfort? Well, Roger Federer put on a majestic masterclass in Miami last night. So I’m happy about that.”
In March, he expressed his admiration for the tennis star again during a discussion about a UK-Swiss trade deal.
“I always say the best thing about Switzerland is not its watches or its financial services or its chocolate.
“The best thing about Switzerland is Roger Federer.”
