London: French First Lady Valerie Trierweiler had been the shared mistress of Francois Hollande, now the country`s Socialist president, and a married conservative minister, Patrick Devedjian, the Daily Mail reported Thursday.
Not only that, she was still married to her husband at the time, it was revealed.
And more controversially still, Hollande was at the time living with Segolene Royal, the mother of his four children and a senior Socialist politician in her own right.
Hollande did not "officially" break up with Royal until after she unsuccessfully ran for the presidency in 2007.
This is the first time that details of 47-year-old Trierweiler`s passionate affair with Right-winger Devedjian, now 68, have been made public.
She was sleeping with Devedjian at the same time as seeing Left-winger Hollande, now 58, according to the newspaper.
Trierweiler was at the time married to her second husband, her fellow Paris Match magazine journalist Denis Trierweiler, with whom she has three sons.
Her divorce was not applied for until 2007, before being sealed in 2010, meaning Trierweiler would effectively have been seeing at least three men at one stage.
Details of the complicated affairs are contained in "La Frondeuse" (The Rebellious One), an unauthorised biography of Trierweiler by French political writers Christophe Jakubyszyn and Alix Bouilhaguet.
Trierweiler frequently asked Devedjian, who is still a senior member of the opposition UMP coalition, to leave his wife of more than 30 years for her, and when he refused she concentrated her affections on Hollande, the Mail said.
Incredibly, Devedjian and Hollande both knew they were sleeping with the same mistress, and developed "a great respect for each other", the newspaper said.
Their affairs were also publicised across France Wednesday, with respected newspapers including Le Figaro and broadcasters carrying the story.
In an interview with French magazine Point Of View, Jakubyszyn said Devedjian and Trierweiler enjoyed "an intimate relationship which lasted a number of years. At the time, both were married. They hesitated in making the big jump, to change their life.
"Patrick Devedjian dilly-dallied so much that Valerie Trierweiler was left to be seduced by a second man from another political side - Francois Hollande," Jakubyszyn said.
Jakubyszyn, who also presents a political programme on French television, said that "little by little, the relationship with Hollande took over the other one".
The mutual loathing between Royal and Trierweiler is regularly highlighted in the French media, especially because Hollande`s live-in lover has her own office at the grand presidential Elysee Palace, while Royal does not even have a parliamentary seat.
A spokesman for the Elysee Palace said that Hollande would not be taking legal action over the book.
Devedjian said he "firmly condemns" what is written in the book, but has yet to make up his mind about legal action.