The Prime Minister avoided a criminal investigation after the police watchdog found no evidence he influenced the payment of thousands of pounds of public money to the American businesswoman, or secured her participation in foreign trade trips he led.
According to the Daily Mail, Ms Arcuri has admitted having an affair with Mr Johnson while he was with his then wife, Marina Wheeler.
“I think that goes without saying,” she is reported as saying. “It’s pretty much out there … But I’m not going to talk about it.”
Ms Arcuri, who is visiting family in Kentucky, told the Mail she felt bombarded by Mr Johnson’s “avalanches of passion”.
When asked if she loved him, she is quoted as saying: “At the time I cared for him very deeply, but I never used the L word. I wouldn’t have recognised being in love.
“I cared very much about this man and I think that’s resolutely clear. That’s all I want to say.”
Downing Street declined to comment.
Ms Arcuri has previously described her first meeting with Mr Johnson in 2011 as "electrifying".
She said the former mayor made up to ten visits to her home office in Shoreditch, and he spoke for free at four events Ms Arcuri hosted with her start-up company, Innotech.3
In 2019 it emerged that Arcuri had received thousands of pounds in public money, including from the mayor’s promotional agency, London and Partners (L&P).
She also joined Mr Johnson on trade missions to New York and Tel Aviv. Her place on the trips was allegedly secured after intervention from Mr Johnson's office, even though she failed to meet the criteria for the trips.
The Independent Office for Police Conduct (IOPC) decided Mr Johnson should not face a criminal investigation.
However, its 112-page report concluded that the prime minister should have declared an interest, and that this failure could have been a breach of the Greater London assembly’s code of conduct.
Its director general, Michael Lockwood, said: “While there was no evidence that Mr Johnson influenced the payment of sponsorship monies or participation in trade missions, there was evidence to suggest that those officers making decisions about sponsorship monies and attendance on trade missions thought that there was a close relationship between Mr Johnson and Ms Arcuri, and this influenced their decision-making.”
The IOPC noted that Johnson has never publicly confirmed or denied an affair with Ms Arcuri. She refused to discuss her private life with the IOPC but she told them there were “always whispers about me from day one”.
Mr Johnson, who was mayor of London from 2008 to 2016, welcomed the IOPC finding at the time, calling the claims against him "vexatious".
Ms Arcuri denied financial wrongdoing to the Mail, saying: “They claim I profited financially from my friendship with Boris … It’s not true.”
City Hall resumed an investigation into Johnson’s conduct after the IOPC closed in May this year.
Ms Arcuri says she has been working on “fictionalised comedy drama about a young American woman and her political encounters in London". She added that plans to return to the UK once restrictions have been lifted.