The parents of 19-year-old motorcyclist Harry Dunn reached an agreement in the damages claim on Tuesday with Anne Sacoolas, the woman charged with causing their son's death by dangerous driving.
UK Foreign Secretary Liz Truss has vowed to continue her efforts to bring Dunn’s reported killer to the UK to face “justice”.
Ms Sacoolas, whose husband was based at RAF Croughton, in Northamptonshire, collided with Mr Dunn when her car veered into the opposite lane of traffic outside the RAF base on August 27, 2019.
After diplomatic immunity was asserted on her behalf by the US government, she was allowed to leave the country.
The Dunn family’s spokesman, Radd Seiger, told the PA news agency a resolution had been “reached successfully between the parties and they can put this part of the campaign behind them”.
Ms Sacoolas was due to give evidence under oath last month as part of the damages claim until a last-minute postponement.
Ms Truss told reporters an agreement in the damages claim was “absolutely not” the end of the matter.
Speaking on the train to Washington where she and a delegation from the British government will meet Joe Biden, Ms Truss was asked if the resolution of a civil case in the UK was the end of the road for efforts to secure Ms Sacoolas’s return.
“Absolutely not. We continue to press for justice for Harry,” she said.
The details of the agreement have not been disclosed, but Mr Seiger said a resolution in the civil claim means Dunn’s family will now turn their focus to the pending criminal case.
Confirming a resolution had been reached in the damages claim, he told PA: “It has come as some considerable relief to them that a resolution to the civil claim has been now been reached successfully between the parties and they can put this part of the campaign behind them.
“It is never easy mounting a legal battle for justice abroad, let alone in the US, but the family’s courage and determination to see this through has been incredible.
He added that the family were supported throughout the claim by former foreign secretary Dominic Raab and that they were very grateful to him as well as the Foreign, Commonwealth and Development Office for their help.
“We have been made aware that the US government made no secret of their displeasure at the British government’s backing of Harry’s family in bringing the claim,” he said.
Ms Truss said she had raised Dunn's case with US Secretary of State Antony Blinken.
Having taken over the role in the Cabinet reshuffle last week, Ms Truss told reporters on the Amtrak train that she would take a “hard-headed” approach on the world stage.
“Harry must get the justice he deserves,” she said.
The damages claim, brought against Ms Sacoolas and her husband, Jonathan, unearthed a great deal of previously unheard material, such as the State Department roles held by the couple at the time of the crash.
The Alexandria District Court in the US state of Virginia heard the pair’s work in intelligence was a “factor” in their departure from the UK, as they left for “security reasons”.
Mr Seiger said: “The family feel they can now turn their attention to the criminal case and the long-awaited inquest into Harry’s death which will follow the criminal case.
“There will also need to be a parliamentary inquiry into this scandal in due course.
“Harry’s family will never be able to move on from his loss, but they are more determined than ever to continue to move forward,” he said.
He called the new developments a “pivotal point” in the campaign but said there was still much work to be done before “justice for Harry can be said to be done".