Downing Street has refused to say if Boris Johnson will give evidence to a Greater London Authority inquiry into whether her acted with “honesty and integrity” in relations with Jennifer Arcuri during his time at City Hall.
Allegra Stratton, the prime minister’s press secretary, insisted that Johnson conducts himself in line with the Nolan Principles – which require holders of public office to act with with honesty and integrity.
But, asked if he would be willing to provide evidence in person or writing to the inquiry, Stratton said the question was “hypothetical”, adding: “Let’s cross all those bridges when they come.”
Johnson’s protracted four-year affair with Arcuri has reentered the spotlight after the American businesswoman revealed the extent of the pair’s relationship.
Arcuri said they met up once a week at the start of the affair, and professed to a mutual “physical and intellectual attraction” with Johnson in a bombshell interview with the Mirror.
She revealed that the pair shared a love of Shakespeare, and that she codenamed Johnson Alexander the Great. The prime minister, she added, “couldn’t keep his hands off me”.
But she accused Johnson of being a “cowardly wet noodle” for not standing by her in a row over her controversial presence on foreign trade trips.
Arcuri, 35, said her romance with Boris, who was Mayor of London at the time, lasted from 2012 to 2016, while he was married to ex-wife Marina Wheeler – the mother of for of his children.
Questions about the pair’s relationship first surfaced two years ago when it emerged that Arcuri was allowed on three taxpayer-funded trade missions led by Johnson.
“We were in an intimate relationship for four years,” she said. “I loved him, and with good cause. But the man I thought I knew doesn’t exist any more.”
Johnson spoke at a series of technology events organised by Arcuri, who was also invited on three taxpayer-funded trade missions led by the then-mayor. Her companies also received £126,000 of public cash in sponsorships and grants.
The GLA probe is to examine whether she was given “preferential treatment”, and whether there was any conflict of interest which should have been declared.
When news of their relationship first became public, Johnson said: “Everything was done with full propriety. There was no interest to declare.”
Questioned about the affair at a daily press briefing in Westminster, Stratton referred MPs to an inquiry by the Independent Office for Police Conduct, which no grounds for a criminal investigation into the prime minister’s actions last May.
But the IOPC report did warn that, if the couple were in an intimate relationship at the time, Johnson would have been “wise” to declare it as a potential conflict of interest, adding: “Failure to do so could have constituted a breach of the broader Nolan principles.”
Stratton added: “Of course the prime minister follows the Nolan principles when conducting himself in public life.”
Asked if Johnson was prepared to give evidence to the GLA’s oversight committee, she said: “I’m just not going to get into these hypotheticals. An independent body has looked at this in depth and found no case to answer.”
Related: Jennifer Arcuri lifts lid on four-year affair with ‘cowardly’ Boris Johnson