The Government has given the go-ahead for a cull of badgers to tackle rising TB rates in cattle, subject to further discussions on exactly how it can be carried out.
Ministers are expected to consult with farmers, wildlife groups, vets and animal welfare charities on revising the guidance to Government agency Natural England to set down the conditions under which it can give out licences for a cull.
The RSPCA has criticised the move, claiming that seven out of ten badgers will be killed.
Scientific experts have said culling badgers, which spread TB to cattle, will only be effective if it is done in a "coordinated, sustained and simultaneous manner".
It would need to be carried out on an area of at least 150 square kilometres (60 square miles), with efforts covering at least 70% of the land within that area.
At least 70% of the badgers on the land targeted, an estimated 1,000 to 1,500 animals, would be culled.
Ideally the area would have boundaries such as coastline or major rivers or roads to stop badgers moving around when the culling disrupts their social structure, which could potentially further spread TB.
The cull would need to be carried out over four years, over a six-week period each year, and with a "closed season" during the winter and spring to prevent orphaned badger cubs being left to starve in setts, or caged badgers suffering from the cold before they are shot.
The costs of the cull will be borne by farmers, who believe that the measure to reduce the rates of TB in cattle herds will save them money overall.
Under the scheme, farmers and landowners could be given licences to trap and shoot badgers, or to carry out "controlled shooting" of free-running animals - a much cheaper option.
But farmers say it will not be a case of individuals simply given the go-ahead to freely shoot badgers on their land.
The National Farmers' Union (NFU) has been drawing up plans which would allow groups of farmers whose land totals at least 150 square kilometres to band together to form limited companies which can then apply for a licence and contract out the culling.
The companies will ensure that farmers contribute their share of the money, stay in the scheme for the required four years and have some measure of anonymity against animal rights extremists who may try and target them.
The NFU said the shooting would be carried out by specially-trained people with firearms licences allowing them to shoot badgers, which in some cases may be farmers contracted by the company representing their area.
The RSPCA has described it as a "black day for badgers".
Farmers have called for action for years but mass slaughter of the animals has polarised opinion, with wildlife campaigners bitterly opposed.
The RSPCA said it believed that at least 70% of the badger population in large areas of the country will be killed, despite the charity saying scientific studies showing that a cull would be of little help in reducing the disease in the long term, and could actually make things worse in some areas.
David Bowles, director of communications for the RSPCA, said: "This is a black day for badgers - a day we have been dreading.
"At a time when the Welsh government has stepped back from a cull, the government in England is slowly shredding its own animal welfare credentials."
The RSPCA said vaccination of badgers, increased levels of testing, improved biosecurity and stricter controls on the movement of cattle were more effective ways of eradicating bovine TB in cattle for good.
Colin Booty, senior scientist for the RSPCA, said: "The RSPCA is sympathetic to farmers struggling to cope with the effects of this crippling disease and thinks that the problem of bovine TB in cattle needs a sustainable and effective solution.
"But this is not such a solution. We believe that the government have taken the wrong fork in the road with this risky policy.
"This cull will contribute little or nothing to the long-term goal of eradicating TB nationally. Instead it will wipe out huge numbers of this much-loved species, including many animals which are healthy."
