The Prime Minister has said the refusal to grant an extradition request for the suspect charged in connection with the death of Harry Dunn is a “denial of justice”.

Boris Johnson’s words have been welcomed by the teenager’s mother, Charlotte Charles, who told the PA news agency they are “words that need action behind them”.

Mr Johnson is the latest senior government figure to criticise the US secretary of state’s decision to reject the request for the return of Anne Sacoolas to the UK – following in the footsteps of the Foreign Secretary and the Home Secretary.

On Monday, Mr Dunn’s parents met with Foreign Secretary Dominic Raab – describing the meeting as “very honest” and “positive”.

Mrs Charles told PA she could see Mr Raab’s “anger” with Mike Pompeo’s decision to reject the extradition request for Mrs Sacoolas.

Mr Dunn was killed when his motorbike crashed into a car outside a US military base in Northamptonshire on August 27 last year.

Mrs Sacoolas, 42, the wife of a US intelligence official based at RAF Croughton, was granted diplomatic immunity after the crash, sparking an international controversy.

The US secretary of state rejected an extradition request by the UK Government for Mrs Sacoolas on Thursday.

On Monday, the Prime Minister’s spokesman told a Westminster briefing: “We believe that this is a denial of justice and the individual concerned should return to the UK.”

Mr Johnson also “reiterated the need” for Mrs Sacoolas to return to the UK during a phone call with US President Donald Trump on Friday.

Reacting to Mr Johnson’s comments, Mrs Charles told PA that he needs to “use his power” to put the pressure on Mr Trump and Mr Pompeo to send the suspect back to the UK.

She said: “The fact that he has come out and said that is obviously a good thing but we hope that he can follow this up with actions now.

“He needs to use his power, because he’s the only person with the power to tell Trump and Pompeo that she needs to come back.

“It feels good that he’s on the same page as us and this is certainly a step in the right direction.”

Asked what her message to the Prime Minister would be, Mrs Charles told PA: “Make the country proud of you. There are a lot of people out there who don’t necessarily have faith in this Government and this is a chance for him to restore a bit of that faith.

“It’s certainly another step forward but until I see action, they are not empty words, but they are words that need action behind them to show us that they are 100% going to stand up for us.”

Harry Dunn’s mother Charlotte Charles
Harry Dunn’s mother Charlotte Charles (David Mirzoeff/PA)

Addressing her views on the meeting with Mr Raab, Mrs Charles said: “Dialogue was very open, everything was very honest, every question we had was answered.

“He was able to look us in the eye, we could see his anger with the decision of the States turning down the extradition request.”

She added: “We didn’t realise how large this would become or how much work it would take but we don’t regret a day of it.”

Mrs Charles and Mr Dunn’s father, Tim Dunn, have disputed the Foreign Office’s claim that the suspect had diplomatic immunity at the time of the road crash.

Mr Pompeo is set to have a meeting with Mr Raab on Wednesday.