Sir Keir Starmer must scrap his promise of an English Right to Roam Act in the event of a Labour government, rural and farming businesses have said.
The Country Land and Business Association (CLA) has written to the Labour leader, arguing that the policy would have 'unknown consequences' for nature, farming and public safety.
The Labour Party announced the plan in January 2023, but the CLA said there had been 'no meaningful engagement' with landowners or farming groups on the subject.
The group, which represents thousands of rural businesses across the UK, said the move would give the public "unrestricted access to virtually all rural land".
The policy "ignores" the need for such land to be protected for the purposes of food production, natural habitats and environmental projects.
It comes as rural support for the Conservative Party has plummeted in recent months, with Labour now taking the lead.
But CLA President Mark Tufnell said an English Right to Roam Act "feels entirely incompatible" with Sir Keir’s stating that Labour was becoming the party of the countryside.
“We already have a fine network of public access," Mr Tufnell said, "140,000 miles of public footpaths exist in England and Wales, as well as 3.5m acres of public access land and significantly more in permissive access.
"Labour should work with us to explore how we might better promote this existing network to those who quite rightly seek access to the countryside, but ensuring it is done in a way that does not damage the landscape."
Mr Tufnell said Labour did not commission any studies in the development of its policy, such as the impact it would have on livestock and the potential damage to crops.
"As far as I can see, Labour adopted this policy because it’s fashionable among some of their voter base, but without really looking into the consequences at all.”
It follows the CLA commissioning polling in 2022, which showed that the public was sceptical about the need of a right to roam.
In the poll, undertaken by Opinium, 69% of the public felt walkers should stick to the footpaths and areas of access land, whereas 21% were in favour of a right to roam.