BORIS Johnson appeared to mock Theresa May by recreating her “naughtiest moment” and running through a field of wheat .

The former Foreign Secretary was pictured out for a jog near his Oxfordshire home while the rest of the Tory party is at the annual conference in Birmingham.

Mr Johnson is set to arrive tomorrow for a rally aimed at making the Prime Minister ditch her Chequers plan for Brexit and fuel his own bid to oust her from Number 10.

And he prepared by going for a jog through a field knee-high with crops, which evoked memories of one of the more bizarre moments from last year’s election campaign.

Asked about her childhood as a vicar’s daughter, the PM told an interviewer she was a “bookish child”.

Asked what was “the naughtiest thing you ever did", Mrs May nervously replied: "Do you know, I'm not quite sure.”

She added: "Nobody's ever perfectly behaved, are they?

"I have to confess when me and my friends used to run through the fields of wheat, the farmers weren't too pleased about that."

It saw the PM widely mocked, and was one of the lasting soundbites from the whole campaign – even sparking its own videogame.

The Scottish Tory leader Ruth Davidson pretended to run through a wheat field, and social media was awash with jokes and memes about her extremely mild indiscretion.

And the Labour leader Jeremy Corbyn blasted her for the admission, saying he was “far too responsible a citizen” to so something similar.

He said: “I grew up in the countryside in Wiltshire and then later in Shropshire.

“I was taught from a very, very early age you walk round the edge of a cropped field. You don’t walk through a field of wheat because it will damage the wheat.”

But despite getting fighting fit for the event on the fringes of the conference in the Midlands tomorrow, Mr Johnson has already come under heavy fire from fellow Conservatives.

After the former Foreign Secretary once again attacked Mrs May’s Brexit blueprint, Chancellor Philip Hammond launched a scathing attack on him.

Dismissing his former Cabinet colleague's Brexit proposals as "fantasy world", he repeatedly said he does not expect him to become PM.

After Mrs May and senior Tories lined up to heap criticism on him, Mr Hammond mounted a sustained assault on Mr Johnson in a newspaper interview and a series of broadcast appearances this morning.

He suggested the ex-London Mayor could not do "grown-up politics" and had "no grasp of detail" on complex subjects like Brexit.

And he mockingly suggested his greatest achievement to date had been introducing the "Boris Bike" cycle scheme in the capital.

The attack came after Mr Johnson used a Sunday Times interview to describe Mrs May's Brexit policy as "deranged" and "preposterous".

In remarks that fuelled speculation about his leadership ambitions, the man who spearheaded the Leave campaign contrasted his position on Brexit with that of Mrs May, who backed Remain, saying: "Unlike the Prime Minister, I fought for this."

But in a round of broadcast interviews today, Mr Hammond was repeatedly asked whether Mr Johnson could ever take the top job, and stated several times: "I don't believe that will happen."

He told Sky News: "Of course, Boris is a big personality, nobody is denying that. What I'm saying is that the business of government is a process of attention to detail, follow-through, lots of hard work.

"It isn't just about making flamboyant statements and big announcements, it's about getting things done."

And he dismissed Mr Johnson’s call for the UK to negotiate a "super-Canada" free trade agreement with the EU, saying: "It isn't about taking back control, it's about fantasy world.”

He told BBC Radio 4's Today programme he added: "When you go into a negotiation you have to understand the position of the people you're negotiating with.

"It's no good just ignoring it and banging your head against a brick wall.

"You have got to understand what their red lines are as well so you can try and find a landing ground you can both accept, which means a deal gets done."