The family of Harry Dunn are to meet Home Secretary Priti Patel as her office considers extraditing the suspect charged with causing the teenager's death by dangerous driving.
Ms Patel's meeting with Harry's mother Charlotte Charles and father Tim Dunn comes just days after the Crown Prosecution Service said they had authorised Northamptonshire Police to charge US citizen Anne Sacoolas.
The CPS said that extradition proceedings had started, noting that the "Home Office is responsible for considering our request and deciding whether to formally issue this through US diplomatic channels".
"Our specialist extradition team will be working closely with the UK Central Authority at the Home Office to do this," the service added.
Dunn family spokesman Radd Seiger tweeted that he was "very much" looking forward to meeting Ms Patel and South Northamptonshire MP Andrea Leadsom "to discuss the tragic loss of Harry".
Sacoolas, the wife of an American intelligence officer, left the UK after the car she was driving was involved in a crash in which Mr Dunn died outside an RAF base in Northamptonshire in August.
The 42-year-old suspect sparked public outrage after claiming diplomatic immunity through her husband's job.
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It was only after she had left the UK on a military flight from the air base that the Foreign Office wrote to the 19-year-old's family to say she did not have immunity.
Following the charging decision, Sacoolas' lawyer Amy Jeffress said her client had "co-operated fully with the investigation" and would not return voluntarily to the UK.
She said: "This was an accident, and a criminal prosecution with a potential penalty of 14 years' imprisonment is simply not a proportionate response."
The State Department has also said the extradition of a former diplomat's wife to the UK would be an "egregious abuse".
However, the Dunns said they took the comments with a "pinch of salt".
Mr Seiger said the lawyer's statement "boggles the mind and is deeply disturbing".
He said: "For Ms Jeffress to seek to undermine one of the most mature, well-developed legal systems in the world, which has fairness at its heart, and which many countries around the world have modelled their legal systems on, is unbecoming of any lawyer, let alone someone of her stature."
He added: "But to seek to gainsay what penalty a judge might hand down, if any, before all the evidence is heard, and to use the maximum possible sentence, which is a matter entirely for the court having heard all the evidence and following clear guidelines laid down by legislators,Read More – Source