Arcuri has declined to confirm or deny a romantic relationship with Johnson, telling Bloomberg News last October that he had been a "good friend" whom she had tutored on technology matters such as how to use Google Hangout.
The IOPC, the British police watchdog, was due to announce its findings later today but British media are reporting it was expected to recommend there be no criminal investigation.
The Greater London Authority said it had alerted the IOPC because Innotech, Arcuri's then-company, had received 11,500 pounds ($19,550 Cdn) from London & Partners, the mayor's promotional agency, for two events in 2013 and 2014.
Boris Johnson will not face a criminal investigation for misconduct.
While its review established that "there may have been an intimate relationship" between Johnson and Arcuri, IOPC "found no evidence to indicate that Mr Johnson influenced the payment of any sponsorship monies to Ms Arcuri, or that he influenced or played an active part in securing her participation in trade missions".
Boris Johnson will not face police investigation over Jennifer Arcuri links but London Assembly probe will resume
The after that mayor would certainly have been "wise" to state a dispute of passion and also the failing to do so might have comprised a violation of the Nolan concepts for criteria of practices in public life, the IOPC stated.
A spokesman for the Prime Minister said the months-long scoping exercise "was a waste of police time".
The comments come as the police watchdog said Mr Johnson will not face criminal action following allegations of misconduct over his relationship with United States tech entrepreneur Jennifer Arcuri, while he was Mayor of London.
Misconduct in public office is a criminal offence with a maximum sentence of life imprisonment.
Last fall, the relationship between Mr Johnson and Ms Arcuri made headlines after news broke that he had possibly used his influence to steer government grants to her tech conference business and get her places on trade missions to Malaysia and Israel.More news: Coronavirus: 30 million vaccine doses 'available in September' if Oxford trial successful
The matter was referred to the watchdog because Johnson was head of the Mayor's Office for Policing and Crime, a role equivalent to a police commissioner, during his 2008-2016 term as mayor.
A spokesperson for the Prime Minister said at the time that Johnson had done nothing wrong.
The London Assembly said it would continue its investigation into Johnson's conduct.
"The oversight committee will take into account the current emergency when looking at the timetable for the investigation".
"That's not our remit and their decision doesn't have any real bearing on our investigation, which will focus on his conduct as Mayor of London", the Chairman of the London Assembly Oversight Committee, Len Duvall, said.More news: Questions Surround Chechen Leader After Reported Hospitalization For Coronavirus
"Such vexatious claims of impropriety in office were untrue and unfounded", the spokesman added.
The case arose from a Sunday Times report saying Arcuri was given money and privileged access while on trade missions that Johnson led as mayor.
And, he added, "it is clear from the evidence that Ms Arcuri's company was not eligible to participate in this mission".
A British phone number listed on the company's website was reportedly being redirected to California.
Arcuri describes herself on her Twitter feed as an entrepreneur and producer.More news: Olivier Sarkozy Apparently Wanted Mary-Kate Olsen to Be a Stay-at-Home Wife