Jennifer Arcuri describes the intimate texts she exchanged with Boris Johnson as "fun" and "mental banter".
The American businesswoman says the pair had a four year affair which coincided with Johnson’s second term as Mayor of London.
At the time, the 56-year-old Prime Minister was married to second wife Marina Wheeler - the mother of four of his children.
Arcuri, 35, says that, in one conversation, she jokingly referred to herself as his “personal penetration tester”.
She said: “Make of our text messages what you will. But I didn’t feel like it was some creepy predator. I never felt that way.
“There are things to be said about how much older he was and married, I can certainly appreciate it. But he was always fun. I enjoyed the mental banter.”
Over the course of the relationship, Jennifer also sent Johnson a string of intimate pictures - but insists they were always classy.
She said: “Most were professionally done - none of them were distasteful.
“I was trying to be very level headed so I wasn’t about to make myself that available. It was every now and then, very tastefully sprinkled in.”
In messages seen by the Mirror, Johnson told her that one of the professional photos was “enough to make a bishop kick a hole in a stained glass window.”
Arcuri said: “That was one of my really very sexy photos. You don’t see me topless, but you see the silhouette of my breast. It’s a pin up kind of look.
“I’d just got the photos back and I thought, ‘Wow, that was fun’.”
Johnson - who won the Tory leadership and became Prime Minister in July 2019 - faces a probe over his relationship with Jennifer during his second mayoral term.
He spoke at four events she organised during this time.
Arcuri was granted access to events at three separate trade missions and has also won a string of grants.
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She’s always insisted Johnson had no influence on this and last year he was cleared of potential criminal wrongdoing.
The Greater London Authority - responsible for the mayor’s office - is investigating claims that his failure to declare his relationship with Arcuri may have been a breach of the Nolan Principles of Public Life, which are contained in the Mayor of London’s code of conduct.
Arcuri was granted access to events at three top level trade missions, despite her businesses not meeting the criteria for the trips.
The Independent Office for Police Conduct said there was no evidence he’d committed the criminal offence of misconduct in public office but he may have breached the Nolan Principles.
Len Duvall, the chair of the GLA oversight committee which is conducting the investigation said: "Our investigation will consider whether Boris Johnson conducted himself in a way that’s expected from anyone in that position.
"It’s important we get those answers, because Londoners deserve to have their politicians held accountable."
Arcuri insists she wasn’t familiar with the rules and now wishes Johnson had declared their friendship in official records.
Reflecting on her liaisons with the married politician, Jennifer said: “Looking back on this, everyone has a story where they feel disappointed in their actions, right?
“But they’ll never be disappointed with what they’ve learned. I can look back and say, 'I should have handled that differently'.”
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