Harry Dunn’s parents have been invited to a meeting at the White House following the diplomatic immunity row involving the suspect in a crash where their teenage son died.
Anne Sacoolas, 42, left the UK just days after the crash which killed the 19-year-old motorcyclist.
She has offered to meet Mr Dunn’s parents, but they say she must promise to return to Britain first.
Mr Dunn, 19, died near RAF Croughton in Northamptonshire on 27 August.
Family spokesman Radd Seiger tweeted: “The White House have just invited #HarryDunn’s parents and I to a meeting this afternoon. Looking forward to getting further answers as we search for #JusticeforHarry.”
Earlier, Mr Seiger said the family’s lawyers, Mark Stephens and Geoffrey Robertson QC, were ready to launch a full investigation into the role the Foreign and Commonwealth Office (FCO) played in the decision to grant immunity to Mrs Sacoolas.
On Monday, Harry’s parents Charlotte Charles and Tim Dunn, gave interviews on US TV after flying to New York in a bid to publicise their case.
They hope media exposure will put pressure on the US government to force Mrs Sacoolas to return to the UK.
Over the weekend, Mrs Sacoolas – who is reportedly married to a US intelligence official who was stationed at RAF Croughton – broke her silence over Mr Dunn’s death in a letter via her lawyers.
In it she said she wanted to meet his parents “so that she can express her deepest sympathies and apologies for this tragic accident”.
Mrs Sacoolas was said to be covered by diplomatic immunity as the spouse of a US intelligence official, though that protection is now in dispute.
On Saturday, Foreign Secretary Dominic Raab wrote to Mr Dunn’s family to explain that the British and US governments now considered Mrs Sacoolas’s immunity irrelevant.
He said the matter was now “in the hands” of Northamptonshire Police and the Crown Prosecution Service.