Animal rights campaigners have accused the government of blocking the publication of a report on the cost analysis of the badger cull.
Dominic Dyer, CEO of the Badger Trust, said Defra had refused to publish the information following a Freedom of Information (FoI) request by wildlife campaigners.
The Badger Trust had requested details of a cost-benefit analysis of the pilot culls in Gloucestershire and Somerset in 2013 and 2014.
Writing on his Twitter account, Mr Dyer accused Defra secretary Liz Truss of hiding the report, which he said showed the culls were a “disastrous, expensive, cruel failure”.
Mr Dyer tweeted: “Government seeks to bury report which proves badger cull has been a disaster on scientific, cost and humaneness grounds.”
It is understood the report included a detailed cost analysis of the third year of culling in Somerset and Gloucestershire and the first year of the “rolled-out” county, Dorset.
Defra said it had decided to withhold the information because it was not in the public interest to release it widely.
A Defra spokesman said: “We recognise that there is a public interest in disclosure of information concerning the badger culls in order to enable the public to assess the quality of policy formulation, advice and guidance, to enhance transparency of decision-making and increase government accountability.
“However, Defra has concluded that the public interest in withholding the information sought outweighs the public interest in its disclosure.
“The assessment of value for money is still in draft form. Defra took a measured approach by extending culling to one additional area this year [Dorset] in order to test lessons learned in a new area and to expand the evidence base that will be used to inform analysis of badger cull cost assumptions and value for money.
“Information from this year’s culls will be used to refine Defra’s cost assumptions in the coming months and releasing an interim assessment before it has been finalised could mislead the public, distract from the discussion of effective disease control and impinge on the safe space officials require to develop the policy.”
Animal activists have claimed that the cost of culling badgers exceeds £7,500 a badger.
But proponents of culling, including the NFU, claim this figure is largely due to the huge costs of policing the culls.
Defra is expected to publish figures from this year’s badger cull later this month.
Last month, NFU leaders told Farmers Weekly they were confident that marksmen had achieved their culling targets across all three pilot counties.
But so far, no official figures have been released to prove or disprove these claims.
Last year, more than 33,000 cattle were slaughtered in the UK due to TB. The government is pursuing a 25-year TB eradication policy in England, which includes tighter cattle controls, badger vaccination in “edge area” counties and badger culling in counties where the disease is rife.