A judicial review is to be held into the Government's decision to allow badgers to be killed in England to halt the spread of bovine TB.
While farmers and the Government have said a cull is necessary to tackle the disease, proposals to kill badgers - which are a protected species - have faced strong opposition from animal welfare and wildlife groups.
The Badger Trust challenged the Department for the Environment, Food and Rural Affairs's proposed cull, saying the move would not prevent the spread of the disease and could in fact increase the numbers of animals affected.
They also claimed that there was a significant cost risk to farmers, and that Defra's cost-impact assessment was "flawed". The third basis for their legal challenge is that Natural England should not have been given responsibility for issuing licences to cull, that function lying with the Environment Secretary.
A spokesman said: "Killing badgers is not one of Natural England's original functions, which are mainly focused on maintaining biodiversity."
Badger Trust's solicitor, Gwendolen Morgan of Bindmans LLP, said: "We are pleased that the court has given the Badger Trust's challenge the green light on all three grounds.
"The badger cull as proposed would make matters worse at great cost to farmers, badgers and rural communities."
No date has been set for the hearing, but the Badger Trust said it was likely to be held at London's High Court in June.
Defra would not comment specifically on the judicial review, citing legal reasons, but said: "Bovine TB is a chronic and devastating disease.
"It forced the slaughter of 25,000 cattle in 2010 alone, and is taking a terrible toll on our farmers and rural communities.
"Nobody wants to cull badgers. But no country in the world where wildlife carries TB has eradicated the disease in cattle without tackling it in wildlife too. We are investing in the development of usable vaccines but sadly these are still years away, and we have to take action now.
"Unless TB is effectively dealt with it will cost taxpayers around £1billion over the next 10 years."