The remark came after the Labour leader called for foreign secretary Dominic Raab to be sacked amid the ongoing diplomatic row over Anne Sacoolas.
Corbyn said: “Now we know the foreign secretary misled the Dunn family who are being denied justice by the US government, will the prime minister commit to his removal from office tomorrow in his reshuffle?”
The Mail on Sunday reported at the weekend that Sacoolas, Harry Dunn’s alleged killer who was granted diplomatic immunity, was a former CIA agent.
Mr Dunn’s family has demanded answers from Raab as to whether he was notified of Sacoolas’s history with the CIA, and if she was still serving at the time of the 19-year-old’s death.
After the “stupid man” comment, and groans from the Tory benches, Boris Johnson, who is expected to shake up his Cabinet on Thursday, responded: “He knows very well that the Foreign Office have been told that Anne Sacoolas was notified to the UK government as a spouse with no official role.
“We will continue without fear or favour to seek justice for Harry Dunn and his family. We will continue to seek the extradition of Anne Sacoolas from the United States.”
Dunn was killed when his motorbike crashed into a car outside a US military base in Northamptonshire on August 27 last year.
Sacoolas, 42, the wife of a US intelligence official based at RAF Croughton, was granted diplomatic immunity following the crash and was able to return to her home country, sparking an international controversy.
She was charged with causing Dunn’s death by dangerous driving in December, but US secretary of state Mike Pompeo rejected an extradition request for her last month.
The Foreign Office today said it has “no plans” to launch a public inquiry into the CIA claims.
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The PA news agency reported it responded to questions from the teenager’s family on Wednesday, insisting the case had been handled “properly and lawfully throughout”.
Dunn’s parents, Charlotte Charles and Tim Dunn, along with family spokesman Radd Seiger, “believe the FCO were complicit” in Anne Sacoolas’s departure – claiming they are “now engaged in a cover-up”.