Nancy Dell'Olio has claimed that her ex-partner and former England football coach Sven-Goran Eriksson was convinced she was having an affair with former Prime Minister Tony Blair.
The 50-year-old Italian lawyer, who was recently voted off Strictly Come Dancing, made the comments in an interview with The Daily Telegraph.
She added that Mr Blair's wife Cherie "was jealous of me from the outset", adding: "And she couldn't help showing it."
Sven, who had affairs while he was in a relationship with Miss Dell'Olio, was "extremely jealous", she claimed.
She said: "Sven was convinced we were having an affair, and it drove him wild. I was careful never to disabuse him of the notion - it was good to keep him on his toes."
She continued: "Tony was wonderful, extremely attractive, one of the best communicators I've ever encountered.
"He was a political visionary who transformed Britain's image in the eyes of the world from fusty and old-fashioned to modern and vibrant."
In a swipe at Cherie Blair, she added: "He had a genius not unlike JFK's. But JFK's wife was bright and beautiful, while Tony's..."
Miss Dell'Olio, who left Sven in 2006, is currently embroiled in a row over her £1.8 million Eaton Place home, which Sven bought prior to their split.
She said: "He is being terrible about it. It's so demeaning."