Following claims that he cast her aside like a gremlin, Boris Johnson says he never got Jennifer Arcuri wet or fed her after midnight.
It is alleged that Mr Johnson was introduced to Ms Arcuri while visiting an antique store in Chinatown during his time as London mayor.
Following allegations about their subsequent relationship, published by The Sunday Times, The Greater London Assembly launched an investigation into claims that Johnson had broken one of the three rules.
In an interview with ITV, Ms Arcuri refused to be drawn on the nature of her relationship with Mr Johnson but said they often met at her flat to read Shakespeare, sometimes staying up and “snacking” into the early hours of the morning.
“We were friends, he used to call me his little mogwai,” Ms Arcuri told ITV, “but then he cast me aside like I am some sort of gremlin.”
Arcuri, a successful US businesswoman, also said that Johnson was fearful of their relationship being exposed to the media spotlight, telling her that he had to be careful and follow all the rules for her safety.
In response to the fresh revelations by Ms Arcuri, the Conservative Party said it considered the decision to refer Mr Johnson to the police watchdog as “vexatious and politically motivated.”
A spokesman added, “We refute the suggestion of any impropriety in office and that Mr Johnson broke any of the rules.
“Ms Arcuri freely admits that the couple’s affair was never exposed to sunlight and there is no evidence to back the suggestion Boris fed her after midnight.
“I also have it on good authority that he most certainly did not get her wet.”