The Badger Trust has said continuing a badger cull in Gloucestershire and Somerset is illegal without independent monitoring and has applied for a judicial review at the High Court.
It claims that the Department for Environment Food and Rural Affairs failed to set up an independent expert panel before allowing the cull in the two pilot areas to continue.
The charity argues that without independent monitoring of the cull it would be unlawful for Defra to make any decisions about rolling out the cull nationally.
Dominic Dyer, chief executive of the Badger Trust and policy adviser at Care for the Wild, said: “The badger cull policy has been a complete and utter failure on scientific, economic and humaneness grounds. There is no justification for continuing with this failed policy which no longer has the confidence of the public, politicians and increasingly the veterinary and farming industry.”
He also called on the British Veterinary Association and members of the 2013 pilot cull independent expert panel to support the legal challenge.
A Defra spokesman said: “Bovine TB is a devastating disease for our cattle and dairy industries, which is why we are determined to do everything we can to combat it.
“Monitoring of the badger culls will continue this year to assess the impact of the changes we are making following the Independent Expert Panel’s recommendations.”
The Badger Trust and Defra were involved in a legal battle in the lead up to the cull, with the Trust attempting to block the pilot culls.