The Assembly has the power to carry out a badger cull even if landowners oppose it, Rural Affairs Minister Elin Jones said today.

The National Trust, which has 50,000 hectares in Wales, has said it would be "unlikely to participate in a voluntary cull'' because of its concern about its scientific basis.

Ms Jones told the Cabinet's weekly press briefing there were "legal opportunities'' to enforce her planned pilot cull if hostile landowners objected to it on their premises.

She said: "This is not particularly new because in the trials in England there were some landowners who were very keen for the cull to happen in the trial area and some who refused.

"So there are precedents in the English trial that will get used in Wales.'' Last July animal health officials needed a court warrant and police back-up to remove Shambo the TB-infected temple bullock from a religious community in Carmarthenshire.

Ms Jones plans to authorise a controversial cull in a bovine TB hotspot as part of an attempt to banish the disease from Welsh cattle herds. The area and the method of culling have not been announced.

Police are investigating after four badgers were found dead in a field near Crymych, Pembrokeshire, last week. Post-mortem examinations suggest they were killed illegally.

Ms Jones warned the badger remained a protected species after the RSPCA raised the possibility that farmers could be taking matters into their own hands.

"There is no Welsh badger cull. There is only a badger cull that will be licensed in a particular bovine TB hotspot in Wales - licensed by me,'' Ms Jones said.

She added: "It is no surprise to us that there will be landowners who don't wish to see a badger cull on their land there will be those who are very keen to see a badger cull on their land.'' She cited the example of the Gelli Aur farming college, near Llandeilo, west Wales, which has not only lost dozens of cows to TB - but also its cat.

Warmly welcomed by farming unions, conservation groups claim a cull will do nothing to stop the spread of bovine TB.