The family of Harry Dunn, a teenage motorcyclist killed in a crash near a US airbase five years ago, say they expect to have a meeting with the foreign secretary next month to discuss an inquiry.
Radd Seiger, the family's spokesperson, said the Foreign Office has told him it will be in touch "with a firm date [in September] soon" for a meeting.
Mr Dunn, 19, from Northamptonshire, died in a crash near RAF Croughton after a car driven on the wrong side of the road by an American citizen collided with his motorbike. The driver returned to the US, causing an international row.
The BBC has contacted the Foreign Office for a response.
Following Labour's election win, the Dunn family called on the party to honour its promise of an inquiry into the government's handling of the case, which caused a diplomatic dispute with the US government.
In 2022, Labour's David Lammy wrote to then Foreign Secretary James Cleverly, demanding an inquiry into the events.
Following the crash in August 2019, the driver of the car, Anne Sacoolas, took advantage of diplomatic immunity and flew back to the US.
The teenager's family campaigned to get Sacoolas back to the UK to face trial.
She was eventually sentenced in 2022, via video link, to eight months in prison, suspended for a year, after admitting causing death by careless driving.
Now the Dunns want to meet new Foreign Secretary Mr Lammy to discuss the appointment of an inquiry chair and the scope of the inquiry.
Mr Seiger added the new Minister for the Americas Stephen Doughty will also "join that meeting".