Dartmoor ponies may have to be electronically tagged before they can be sold, under proposed legislation.
Hundreds of Dartmoor ponies are rounded up and sold every autumn
The European Union has suggested foals are identified by a microchip before the owner applies for a passport.
But the Dartmoor Commoners' Council has opposed the idea and says it could be detrimental to the breed.
The council says microchipping the Dartmoor ponies would cost more than they are worth and because the animals are wild it could be dangerous.
The Department for Environment Food and Rural Affairs (Defra) said it has consulted a number of organisations, including the Dartmoor Commoners' Council, and is considering its reservations.
Hundreds of animals are rounded up during the Dartmoor pony drift every autumn and sold at auction.
Last year farmers paid £1 towards to the £30 cost of the pony passports. The remainder was paid for by the buyer.
Each pony sold must have a passport to protect human health in the countries where horse meat is eaten.