Britain's prosecutors have authorised police to charge Anne Sacoolas with causing death by dangerous driving.
British prosecutors have begun extradition proceedings against the wife of an American intelligence officer after ruling that she is to be charged with causing death by dangerous driving.
The Crown Prosecution Service (CPS) announced that it had authorised Northamptonshire Police to charge Anne Sacoolas with killing Harry Dunn, 19, in a road collision in August.
Sacoolas, whose husband was stationed at a nearby air force base used by the United States, claimed diplomatic immunity and left Britain shortly after the crash.
She later admitted through her lawyers that she was driving on the wrong side of the road when the collision took place.
Dunn's family have called on her to return to the UK voluntarily and met US President Donald Trump as part of a campaign for justice. They have also filed a complaint against the UK Foreign Office for allowing Sacoolas to claim diplomatic immunity.
"The Director of Public Prosecutions has met with Harry Dunn's family to explain the basis of the decision we have made following a thorough review of the evidence available," the CPS said on Friday.
The UK Foreign Office has since launched a review of immunity arrangements for US personnel stationed at the Croughton Royal Air Force base.
Foreign Minister Dominic Raab, who met the Dunn family on Tuesday, appealed to Sacoolas "to do the right thing."
"I urge her to come back to the United Kingdom and co-operate with the criminal justice process," he added.
The US State Department said in a statement to Sky News on Friday: "We do not believe that the UK's charging decision is a helpful development" but that it would "continue to look for options to move forward."