Jennifer Arcuri says she first got intimate with Boris Johnson just hours before he was pictured sitting with his wife and the Royal Family.
Last night, she revealed in a world-exclusive interview with the Sunday Mirror how their affair lasted four years.
And they first had sex just hours before he was pictured sitting between his now ex-wife, barrister Marina Wheeler and Princess Anne at the opening of the 2012 London Paralympics.
Jennifer said the Prime Minister turned up at her flat in Shoreditch High Street in his mayoral suit and Olympic badges.
The US businesswoman, 35, said she was "completely in control," adding: "I could tell this man was so excited beyond words to see me. It gave me the upper hand.”
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Just hours later, Boris attended the Paralympics opening ceremony where he was pictured alongside Prince William and Kate Middleton, as well as Princess Anne.
A crowd of 62,000 crammed into the Olympic Stadium in Stratford, east London, to watch the incredible opening ceremony.
And a worldwide audience of one billion tuned in as athletes from 166 nations followed their nation's flag for a circuit around the stadium.
But Jennifer says Boris was texting and calling her all night as she saw him on the television, describing it as "bizarre."
The Prime Minister is now facing a slew of questions over whether he breached a code of conduct.
A probe is set to examine whether Jennifer received any “preferential treatment” and if there was any conflict of interest.
The 35-year-old says the Prime Minister didn't want to leave her flat after they had sex - and she had to find his lost socks ahead of his TV appearance.
She said: “He didn’t want to leave, very clearly. It was awkward – you’re supposed to be on stage and on TV in a few hours. Now, I’m pushing you out the door with all of your mayoral bric a brac, the lanyard with the big badge, and the lapel pins.
"He was very clearly distraught because he wanted to stay. I think I couldn’t even find his sock – it was just the most bizarre experience."
Read Jennifer Arcuri's full story in the Sunday Mirror, in shops today.
