Prosecutors have begun extradition proceedings against the wife of a US intelligence agent who left Britain following a road accident in which a British teenager was killed.

Anne Sacoolas returned to America claiming diplomatic immunity after she allegedly collided with a motorbike been ridden by 19-year-old Harry Dunn on August 27.

Even though Mrs Sacoolas has left the UK, the Crown Prosecution Service (CPS) yesterday authorised Northamptonshire Police to charge the 42-year-old with one count of causing death by dangerous driving - an offence that carries a maximum sentence of 14-years.

Speaking after the announcement, Harry’s mother, Charlotte Charles, described it as a “huge step” towards getting justice for her son.

Mrs Charles said: “We feel that we have made a huge step in the start of achieving the promise to Harry that we made.

"We made that promise to him the night we lost him to seek justice thinking it was going to be really easy.

"We had no idea it was going to be so hard and it would take so long but we feel it is a huge step towards that promise we made Harry."