Professor Chris Whitty had the perfect comeback to the young man who called him a liar in the street saying he hopes he becomes a “model citizen” and like the late Captain Sir Tom Moore.

Shocking footage emerged on social media showing the youth taunting England's chief medical officer as he appeared to wait for a lunch order from a street stall.

The footage is believed to have been taken at Westminster’s Strutton Ground Market and has been uploaded to TikTok.

In the video, the young man repeatedly calls Professor Whitty a liar, and adds: “You lie about the Covid-19 cases… stop lying to the TV, man”.

At one point, the man filming the professor turns the camera around to show his face.

Asked about the incident at the Downing Street press conference on Wednesday, Prof Whitty said: “In terms of being harangued … the odd young lad showing off occasionally happens.

“I didn’t think anything of it frankly, I was very surprised it was picked up by the media at all, as anything of any importance.

“I’m sure he’ll become a model citizen in due course and hopefully more like Captain Tom, who was the kind of person who I think much more exemplifies the spirit of the UK.”

Inspirational veteran Sir Tom, who died aged 100 on Tuesday morning, raised more than £32 million for the NHS during the first coronavirus lockdown.

Prof Whitty added: “He was himself clearly absolutely remarkable, but what he was also doing was showing how it is that everybody has responded to this (the pandemic), and this has been a nationwide everybody responding.

“If it wasn’t for that – we would not see those numbers coming down.”

He added: “That is because everybody has worked together.”

Boris Johnson was clearly entertained by the comparison and cheered the remarks in scenes reminiscent of a fiery Commons debate.

But earlier Downing Street branded the verbal attack on Prof Whitty as “unacceptable”.

Prime Minister Boris Johnson’s official spokesman said: “Chris Whitty is an outstanding public servant who has worked incredibly hard and tirelessly to help steer us through what has been a very, very challenging time over the past year.

“And it is clearly unacceptable that somebody who has done so much is being subject to this sort of behaviour.”

The catcaller who confronted Prof Whitty in the street was also labelled “pathetic” by Health Secretary Matt Hancock.

In the footage, the young man, who is holding the camera, walks around Prof Whitty, telling him: “Liar. You’re a liar. Mandem is a liar. You’re a liar. You lie about the Covid-19 cases. Stop lying to the TV, man.”

It is unclear when the video was taken, but Prof Whitty stayed calm and did not respond to the taunts as he waited for food from a nearby market stall.

Speaking to BBC Breakfast, Mr Hancock said: “I think the individual concerned is pathetic, I think it is ridiculous what he is doing.

“Chris Whitty is one of our greatest living scientists and his advice to the Government all the way through this, and his advice to all of us in the population, has been incredibly smart and thoughtful, and he is a great asset to this nation.

“The idea that someone would do something as silly as that is ridiculous.”

He added: “Chris Whitty is a scientist of great repute and, frankly, he should be respected by everybody.”