The Foreign Secretary was “cold” and “rude” to the family of Harry Dunn during a meeting about the teenager’s death, their spokesman has said.

Dominic Raab met the 19-year-old’s parents, Charlotte Charles and Tim Dunn, last week.

The teenager was killed when his motorbike was involved in a head-on collision outside RAF Croughton in Northamptonshire in August.

Harry Dunn death
Harry Dunn (Family handout/Northamptonshire Police/PA)

His parents met Mr Raab after Anne Sacoolas, the motorist allegedly responsible for the crash, was given diplomatic immunity and allowed to flee to the US after the crash.

Family spokesman Radd Seiger told the PA news agency: “They were twitchy (at the meeting with the family). There were three lawyers in the room – why would you bring three lawyers into a room with a grieving mother? Why?

“There were 12 people in a room – for a meeting that was supposed to be him expressing his condolences.

“He (Mr Raab) was stiff, he was cold, he was unpleasant, he was rude. Then three days later we get another letter.

“That isn’t right.”

Harry Dunn death
Family spokesman Radd Seiger flanked by Harry Dunn’s mother, Charlotte Charles, and father, Tim Dunn, speaking to the media after meeting Dominic Raab at the Foreign Office in London (Jonathan Brady/PA)

His comments came as the family demanded an investigation over the Foreign Office’s (FCO) advice to Northamptonshire Police that Ms Sacoolas had diplomatic immunity.

They are demanding to see all emails, messages and notes sent in relation to her immunity status.

Speaking in New York, Mr Seiger said: “We want to conduct an investigation into the FCO’s decision to advise Northamptonshire Police that this lady had the benefit of diplomatic immunity.

“What we don’t know is whether somebody cocked up or whether they were put under pressure by the Americans to concede.”

If they are not happy with the documents, the family say they will then ask for a judge’s opinion on the lawfulness of the FCO’s decision.

Mr Seiger added: “If we’re not satisfied, then we’ll go to a judicial review and ask a High Court judge to review it all.”

On Saturday, before the family left for the US, they received a letter from Mr Raab, saying that Mrs Sacoolass, 42, no longer had immunity.

“The letter is worded very carefully, they’re not saying it’s just a change of heart – they are saying that it’s an evolution,” said Mr Seiger.

He also said that the family’s lawyers, Mark Stephens and Geoffrey Robertson QC, believe “they’ve (the FCO) been lying to you”.

Ms Charles and Mr Dunn said: “We were astonished last Saturday to receive the hand-delivered letter from the FCO indicating that Mrs Sacoolas did not in fact have diplomatic immunity.

“We were still reeling from our terrible meeting with Dominic Raab, Foreign Secretary, last Wednesday, just three days earlier, where he was adamant that Mrs Sacoolas did have immunity.

“Something is not right.

“We will not rest until we get the truth. We will not let Harry passing be in vain.”

Mrs Sacoolas has said she is “terribly sorry” about the incident and that she had “no time to react” when she saw Mr Dunn’s motorbike.

Harry Dunn death
A green ribbon tied to a tree in memory of Harry Dunn (Steve Parsons/PA)

The FCO has been contacted for comment.