- Video report by ITV News Correspondent Neil Connery
The father of Harry Dunn, the teenager killed in a collision outside a military base in Northamptonshire in August, confronted Dominic Raab on Monday night as he arrived at an election hustings.
Tim Dunn asked to speak to Mr Raab as the foreign secretary pulled up outside the venue in an attempt to put pressure on him.
The family continue to fight for justice after the main suspect, Anne Sacoolas, a wife of a US intelligence official who was based at the RAF base, sought diplomatic immunity and fled the country.
The foreign secretary has been criticised by Harry's parents for his handling of the case.
Mr Raab has previously admitted the Foreign Office asked Northamptonshire Police to delay telling Mr Dunn and Harry's mother Charlotte Charles that the woman involved in the crash that killed their son had left the UK.
In reply to Mr Dunn's request to speak to him, Mr Raab said: "Do you know what, I'm very happy to see you any time, but I better go in there for the hustings. I'm really happy to come and see you anytime."
As Mr Dunn repeated his request, Mr Raab said it was "not on" Harry's father had confronted him "right in front of the cameras".
Mr Raab said he "did not want to keep the other people waiting" and Mr Dunn could call him another time - claiming to have given him his phone number despite Mr Dunn insisting he had not.
"You didn't gives us your phone number at all," Mr Dunn responded.
"We feel he's lied to us two or three times in meetings and in statements he's made in the Commons," Mr Dunn said outside the hustings.
"And we feel that people should know how he really is as a gentleman and how he comes across to us as our family."
Mrs Sacoolas is believed to have been driving on the wrong side of the road when she hit 19-year-old Mr Dunn’s motorbike outside RAF Croughton on August 27.
Mrs Sacoolas claimed diplomatic immunity after the incident and returned to the US, sparking international controversy.
On Monday night, Mr Dunn and Ms Charles appeared to be in the group of people who were not allowed entry into the church due to overcrowding.
A sign held up against the glass on the front door said: "Harry Dunn's parents are here and need to come in."
People were reportedly denied entry due to "fire safety concerns".
Mr Raab was again confronted by Harry's family and friends as he left the building and was ushered into his official car.
A number of police officers and security staff were stopping people from blocking the exit, with Mr Raab booed and heckled as he drove away.
In October, a Foreign Office spokesperson said: “We have done everything we can properly to clear a path so that justice can be done for Harry’s family.
"As the Foreign Secretary set out in Parliament, the individual involved had diplomatic immunity whilst in the country under the Vienna Convention on Diplomatic Relations. We will respond to any legal action in due course."