BORIS Johnson has refused to back any Tory leadership candidates in his first public appearance since he resigned as Conservative leader.

Speaking during a visit to the Francis Crick Institute in London, he wouldn't discuss the mass exodus of ministers which prompted him to announce he'd be stepping down.

The Tory chief said throwing his weight behind one of the candidates to succeed him could “damage” their chances.

Following the accusation in his resignation speech that his tormentors had succumbed to a “herd mentality”, he was asked whether he felt betrayed during a visit to the Francis Crick Institute in London.

Johnson said: “I don’t want to say any more about all that.

He told reporters: “I’m determined to get on and deliver the mandate that was given to us, but my job is really just to oversee the process in the next few weeks, and I’m sure that the outcome will be good.

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“We just need to get on and as I said I think before to you, the more we focus on the people, on the people who elect us, on their jobs, their hopes and what they can get out of investment in science and technology.

“The more we talk about the the future that we’re trying to build, the less we talk about politics in Westminster, the generally happier we will all be.”

The National:

“There’s a contest under way and it’s happened, and, you know, I wouldn’t want to damage anybody’s chances by offering my support.

“I just have to get on and, in the last few days or weeks of the job, the constitutional function of the Prime Minister in this situation is to discharge the mandate, to continue to discharge the mandate, and that’s what I’m doing.

“I think the reason we’re here today is because I think … science, technology – our natural genius in this area is one of the many, many things that is going to carry us forward and make sure that our our future is very bright.”

His appearance came amid speculation that Johnson may give controversial Culture Secretary and Boris-loyalist Nadine Dorries a peerage in his final honours list.

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On Monday, Downing Street said it is “convention” for prime ministers to award knighthoods and appointments to the House of Lords in a resignation honours list, without giving details of Johnson’s potential picks for titles.

The outgoing Prime Minister’s official spokesman said: “I don’t have an update for you on that definitively. I’ve seen sort of speculation.

“It is convention – individuals who can be nominated in recognition of their public or political service and prime ministers draw up those sorts of lists, but I don’t know specifically on that at this point.”

Asked about reports that Johnson’s list could be long, the official said: “I don’t believe there have been any significant discussions on it at this stage.”

He also said he was “not aware” of Johnson planning to give his father, Stanley Johnson, a knighthood.