The Foreign Secretary has raised the case of Harry Dunn with the US secretary of state ahead of a court hearing in Virginia, the Prime Minister has said.

The Alexandria district court in Virginia is expected to set a timetable for Mr Dunn’s alleged killer to give evidence in a civil claim for damages against her on Wednesday.

In February, a judge ruled the substantive claim against Anne Sacoolas can go ahead in the US, despite the suspect’s motion to dismiss it.

While making the application, lawyers acting on behalf of Sacoolas made admissions about the 43-year-old’s employment at the time of the road crash which killed Mr Dunn – saying she and her husband Jonathan worked for the US state department and “fled” the UK due to “issues of security”.

The US government asserted diplomatic immunity on behalf of the suspect following the 19-year-old’s death in August 2019 outside RAF Croughton in Northamptonshire, and she was able to return to her home country.

She was charged with causing death by dangerous driving, but an extradition request, submitted by the Home Office, was rejected by the US state department in January last year.

The PM confirmed to the Dunn family’s constituency MP Andrea Leadsom on Wednesday that the UK Government continues raise the case “at the highest level”.

Asked at Prime Minister’s Questions if he could try to persuade President Joe Biden to deliver justice for Mr Dunn, Boris Johnson said: “She’s completely right to continue to raise the case of Harry Dunn and we sympathise deeply with his family.

“It’s a case that we continue to raise at the highest level and I know that my Right Honourable Friend the Foreign Secretary has only just raised it now with Tony Blinken, the US secretary of state.”

On Wednesday, Sacoolas’s legal representatives will submit motions to dismiss certain parts of the civil claim – including an application to pay compensation amounting only to Mr Dunn’s funeral costs.

The Dunn family also brought the damages claim against Mr Sacoolas, due to Virginia’s laws suggesting he is liable for allowing his wife to use the car which killed the teenager.

Judge Thomas Ellis allowed the case to remain in the US and dismissed Sacoolas’s application against the substantive civil claim, citing her “refusal” to return to the UK.

Handing his judgment down last month, the judge said: “While it is commendable that defendant Anne Sacoolas admits that she was negligent and that her negligence caused Harry Dunn’s death, this does not equate acceptance of responsibility.

“Full acceptance of responsibility entails facing those harmed by her negligence and taking responsibility for her acts where they occurred, in the United Kingdom.”

After throwing out Sacoolas’s motion to dismiss, Judge Ellis is expected to set a timetable on Wednesday for the suspect to give evidence in a “deposition” ahead of a trial to be held in Virginia later this year.