Media playback is unsupported on your device Media caption Jennifer Arcuri: "I'm not going to put myself in a position where you can weaponise my answer"

A US businesswoman at the centre of a row over whether Boris Johnson failed to declare a conflict of interest says he never showed her "any favouritism".

Jennifer Arcuri also refused to say whether the pair had an intimate relationship when he was London mayor.

Ms Arcuri told ITV's Good Morning Britain that Mr Johnson spoke at events she ran and came to her flat - also her office - "a handful" of times.

The PM denied breaking any rules of conduct, but would not comment further.

He has insisted everything was done "entirely in the proper way".

But Labour's shadow chancellor, John McDonnell, said Mr Johnson - who served as mayor between 2008 and 2016 - "had a duty" to declare their friendship.

"Regardless of the exact nature of his relationship with [Ms] Arcuri, it is clear that she and Boris Johnson were close, and that he misled the public when he said there was no interest to declare," he added.

The code governing conduct at London City Hall states that public office holders should not act in any way to gain benefits for families or friends, and should declare private interests to resolve any conflicts.

But speaking after Ms Arcuri's interview, Mr Johnson said he had not broken the code, adding: "I think I have said everything I am going to say on that matter."

'Good friend'

The story first emerged in the Sunday Times, with claims technology entrepreneur Ms Arcuri had joined trade missions led by Mr Johnson and received thousands of pounds in public money.

It is understood she attended events on two of the trade missions - to New York and Tel Aviv - despite not officially qualifying for them as a delegate.

The newspaper reported that one of her businesses received £10,000 and £1,500 in sponsorship money from a mayoral organisation when Mr Johnson was mayor, as well as a £15,000 government grant for foreign entrepreneurs to build businesses in Britain.

The newspaper claimed she had received favourable treatment due to her friendship with Mr Johnson.

But Ms Arcuri insisted he was just "a really good friend", and "categorically" had "nothing to do with my other achievements".

"Boris never, ever gave me favouritism. Never once did I ask him for a favour. Never once did he write a letter of recommendation for me. He didn't know about my asking to go to trips," she told ITV.

The current London Mayor, Sadiq Khan, has launched an investigation into the allegations at City Hall, and the Greater London Authority's Oversight Committee has given Mr Johnson 14 days - ending this week - to explain his relationship.

Mr Johnson has also been referred to the police watchdog, who will consider whether there are grounds to investigate the prime minister for the criminal offence of misconduct in public office.

Media playback is unsupported on your device Media caption Boris Johnson: 'Everything has been done with full propriety'

Asked repeatedly on the ITV breakfast programme whether she was having an affair with Mr Johnson when he was mayor, Ms Arcuri refused to answer.

"I am not going to be putting myself in a position for you to weaponise my answer," she said.

She did confirm he had visited her home - which was also her office - "five, 10, a handful of times", but added: "It's really not anyone's business what private life we had."

They had tried to meet in public, she went on, but it "became too much of a mob show".

"So I said 'you just have to come to my office.'"

'Waste his time'

On the issue of trade missions, Ms Arcuri said she had access because of the work she was doing - not because of any relationship with Mr Johnson.

"At the end of the day, I was allowed to go on that trade mission as a delegate because of who I was," she said.

Ms Arcuri said she had never discussed any sponsorship or grants with Mr Johnson, and asked if he had helped with any "sponsorship money", she said: "Categorically no. Do you think I would waste his time talking about this stuff?"

She also said Mr Johnson had nothing to do with an additional £100,000 grant awarded to her company by the Department for Culture, Media and Sport in January.

And she denied reports he had written her a letter of recommendation to run the taxpayer-funded Tech City organisation, promoting technology companies in east London.

Politically, this interview still leaves the big question hanging out there - did Boris Johnson use his influence or seek to intervene in any way to help Jennifer Arcuri secure grants or to go on trade delegations?

What we did learn was that she was most certainly a very, very close friend.

Why that matters is because if there is any suggestion - or proof, more importantly - that Mr Johnson did intervene on her behalf, then he would have had to declare that she was a friend.

And that is the missing piece of the jigsaw.

We don't know whether Boris Johnson did seek to use his office in any way to lean on city officials to get her on those trade trips or to also get her the grants.

We do know that he went to speak at a number of events she organised and we do know that Boris Johnson was on three of the trade trips she was on.

So that raises the question that, in any case, should he have declared he was a close friend of Ms Arcuri's?

There will be a lot of headlines about her refusal to deny they had a relationship, but in terms of the politics, the big question is still to be answered on whether he intervened on her behalf because of their relationship.

Ms Arcuri told Good Morning Britain the pair shared "a love" and "passion" for Shakespeare and literature during their friendship.

"Boris is extremely personable. He cares a lot about this country, and he cares a lot about people... he is a guy you want to hang out with."

Asked whether she ever loved Mr Johnson, she said: "I've been asked that many times. And I care about him deeply as a friend, and we do share a very close bond, but I wish him well.

"I really do want him to focus on making Britain great again."

Who is Jennifer Arcuri?

Jennifer Arcuri describes herself on Twitter as an entrepreneur, cyber security expert and producer.

She began her career as a DJ on Radio Disney, before moving into film - where she wrote, produced and directed a short film that went on to be sold at Cannes Film Festival.

Ms Arcuri then brought in her tech skills to create a streaming platform for independent film makers.

But it was her founding of The Innotech Network in London that saw her path cross with Boris Johnson.

The network hosts events to discuss tech policy, and Mr Johnson was the keynote speaker at the first of those in 2012.

Since then, Ms Arcuri has also founded another company called Hacker House, which uses ethical hackers to find tech solutions for businesses.