Environment Secretary Hilary Benn will today kick off a campaign to support the fox-hunting ban amid fears from supporters of the legislation that a Tory government would scrap it.

In a sign of how concerned the anti-hunting lobby is about the future of the ban, Mr Benn will spearhead an awareness-raising drive about the Conservatives' plans.

The campaign, urging people to demonstrate their support at www.backtheban.com, comes as opponents of the 2004 anti-hunt law step up protests on their traditional Boxing Day outings.

Both the New Foreat Hounds and the Hursley and Hambledon Hunt are staging their annual events today.

The campaign will be seen as another attempt by Labour to stress the dividing lines between themselves and the Tories ahead of next year's general election.

The campaign is supported by the actors Patrick Stewart, Jenny Seagrove and Tony Robinson.

Conservative leader David Cameron has promised a free vote on the repeal of the Hunting Act, saying he believes it ''doesn't work'' and ''doesn't make sense''.

Labour claims Tory agriculture spokesman Jeremy Hunt is bankrolled by critics of the ban. He has described the law as ''an affront to civil liberties'' and ''completely unworkable''.

Under the Act, which came into force in 2005, the hunting with dogs of all wild mammals is an offence.

However, it does not stop people riding with their dogs altogether. Today's hunts will follow artificial trails.

But if foxes have been killed by hounds, a defence of lack of intention has usually protected huntspeople. There are other loopholes, too, which have been exploited.

Only nine prosecutions of traditional hunts have reached court since 2005, with three convictions.

Mr Benn said: ''For David Cameron, getting the Act repealed is a priority.

''He used to hunt foxes; he talked about fox hunting in his first ever speech to Parliament; and he has said that if he becomes prime minister he will get rid of the fox hunting ban.

''But, like the vast majority of people, I think that the barbaric act of letting dogs tear foxes to pieces shouldn't return to our countryside.''

He added: ''If you think the Tories have changed, their views on fox hunting with dogs make it absolutely clear that their priorities haven't.''