The Duchess of Cornwall has lost a planning battle over her neighbour’s proposals to build a granny flat.

The duchess, whose country retreat is the grade II-listed Ray Mill House in Wiltshire, used the estate manager at Highgrove, which belongs to the Prince of Wales, to mount three objections to the plans.

Phil Clayton, whose home The Old Mill shares a private lane with the duchess’s house, applied to demolish an outbuilding next to his home and build a flat for his elderly mother.

The letters of objection to the council were written on Highgrove-headed paper by Charlie Craven, who is described as estate manager to the Prince of Wales and the Duchess of Cornwall. Despite her objections, Wiltshire council has approved the plans for