The US diplomat's wife involved in a crash which killed teenager Harry Dunn does not have diplomatic immunity, the Foreign Office has said.
Harry's parents Charlotte Charles and Tim Dunn were informed of the development in a letter from the Foreign Secretary Dominic Raab.
It reads: "The question remains when such immunity comes to an end, regardless of any waiver.
"We have looked at this very carefully, as I wanted to be confident in the position before conveying it to you.
"The UK government's position is that immunity, and therefore any question of waiver, is no longer relevant in Mrs Sacoolas' case, because she has returned home.
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"The US have now informed us that they too consider that immunity is no longer pertinent.
"In these circumstances, Harry's case is now a matter for Northants police and the CPS to take forward.
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"That of course is done entirely independently, and it would not be right for me to comment any further."
It comes after Anne Sacoolas said she wanted to meet Harry's parents to "express her deepest sympathies and apologies".
Harry, 19, died when his motorbike collided with a car outside an RAF base in Northamptonshire in August.
Anne, 43, was involved in the crash but returned to the states after being granted diplomatic immunity.
Her statement read: "Anne is devastated by this tragic accident. No loss compares to the death of a child and Anne extends her deepest sympathy to Harry Dunn's family.
"The media reporting has been inaccurate in many respects. To begin with, Anne fully cooperated with the police and the investigation.
"She spoke with authorities at the scene of the accident and met with the Northampton police at her home the following day. She will continue to cooperate with the investigation.
:: A Family's Fight – Sky News' special report on the Harry Dunn case will air at 3.30pm on Sunday
"Anne would like to meet with Mr Dunn's parents so that she can express her deepest sympathies and apologies for this tragic accident.
"We have been in contact with the family's attorneys and look forward to hearing from them."
Mrs Sacoolas' lawyer had earlier contacted the Dunn family's spokesperson Radd Seiger, who is in Washington.
Mr Seiger told Sky News: "It's a great sign (Mrs Sacoolas' lawyer has) reached out to us and we will be engaging in embracing those discussions as openly and as positively as we always do."
He added that Harry's parents see any development in the case as a "positive step forward" and the lawyer making contact was "undoubtedly a positive step forward".
Mr Seiger also said he was "crystal clear" that Ms Sacoolas "does not have the benefit of diplomatic immunity", and continued: "Why then did the British government advise Northamptonshire Police that she did have diplomatic immunity, and they therefore could not undertake any inquiries?
"They couldn't speak to her, arrest her, let alone charge her."
Mr Seiger added: "Something's gone wrong with the family disappearing seemingly overnight."
The family spokesperson had also said it was unlikely HRead More – Source