Prince Andrew will wear military uniform for the final vigil around the Queen's coffin during the lying in state at Westminster Hall - but not for her funeral or other ceremonial events in the coming days.
The disgraced royal was stripped of all of his honorary military roles in January, including Colonel of the Grenadier Guards, after the furore over his friendship with paedophile billionaire Jeffrey Epstein.
The Duke of York paid millions to settle a civil sexual assault case with Virginia Giuffre, a woman he claimed never to have met.
He denied all her claims.
Andrew, a former Royal Navy officer who served in the Falklands War, retained his rank as a Vice Admiral.
While working royals including the King, the Prince of Wales, the Princess Royal and the Earl of Wessex will parade in military uniform at the state funeral next Monday and on other occasions in the coming week, Andrew will not, apart from at the vigil.
As a non-working member of the Royal Family, the Duke of York will wear uniform as a special mark of respect for the Queen at the vigil in Westminster Hall, sources said.
It has not yet been confirmed whether the Duke of Sussex - also a non-working royal - will wear military dress.
At the Duke of Edinburgh's funeral in April 2021, the issue of military dress was dealt with by the Queen, who decided that no members of the Royal Family should wear uniform.
It was a break with tradition but seen as the most eloquent solution to a host of problems.
Reports had suggested Andrew was considering wearing the uniform of an admiral.
He was due to be promoted to Admiral in 2020 to mark his 60th birthday but this did not go ahead following the fallout from his disastrous Newsnight appearance.