A figure from a famous nursery rhyme has been caught up in a safety row.
Members of the protest group trained the horse for the march
The "fine lady" character from the "Ride A Cock Horse" rhyme is being prevented from riding her horse to Banbury Cross because police object.
A white horse had been specially trained to lead a protest march over plans to downgrade key services at the Oxfordshire town's Horton Hospital.
Instead, the march on Friday evening is now likely to be taken over by a mock horse ridden by a man in a dress.
Up to 5,000 people were expected to follow the "fine lady" on the march in protest at plans to move the bulk of the maternity and paediatrics services to Oxford's John Radcliffe Hospital, 25 miles (40km) away.
A team from the Save The Horton Campaign trained the horse and made a gown for the "fine lady" to wear.
Campaign spokesman Charlotte Bird said: "It's ridiculous - people are gobsmacked.
"We've had a risk assessment done. A horse has more right to ride down a public road than cars have. People in the horse fraternity are outraged at this."
Police said they have not actually banned the horse from being ridden through the town - but they have strongly advised against it, on grounds of animal welfare and public safety.
Lead organiser George Parish said the police stance would not lead to a change in tactics by protestors.
But he praised the police for their efforts to ensure the march could go ahead.
Instead, the march will be led by Stephen Wass, head teacher of St Mary's Primary School in Banbury, wearing a blue gown and with a large mock horse strapped to his waist.