David Cameron was jeered in the House of Commons as he claimed Andy Murray was the first British player to win Wimbledon in 77 years.
Labour MPs heckled the Prime Minister who had forgotten that Murray was only the first British man to win Wimbledon in 77 years - Fred Perry won the men's singles competition in 1936.
The last British champion in the singles at Wimbledon was Virginia Wade in 1977 in the women's competition.
Mr Cameron told the Commons: "Before listing my engagements, I am sure the whole House and indeed the whole country will wish to join me in congratulating Andy Murray on his historic Wimbledon success.
"To become the first British player to win Wimbledon for 77 years is a fantastic achievement and will rightly go down in our history books."
Labour leader Ed Miliband picked up on the gaffe. He said: "Let me first join you in paying tribute to Andy Murray for his fantastic victory following Virginia Wade's victory in 1977.
It was a fantastic achievement. He showed extraordinary determination and the whole country is incredibly proud of him."
A Downing Street source said the Prime Minister's mistake was "not the worst crime in the world".