The demonstrators are asking for a Bill bringing in a ban on fox hunting to be included in the Queen's Speech.

Organisers London Animal Action say they expect several thousand campaigners to join the protest. Many will go into the Commons to lobby their MPs.

Veteran Labour MP Tony Benn, a long-time campaigner against hunting, is due to address the crowd.

A fox cub discovered trapped in a cage

The campaigners point out that Labour pledged before the election to ban on fox hunting with hounds and now want the government to fulfil the promise.

'Delayed by Lords'

Paul Thompson of Animal Action said: "Labour are fudging the issue. They've said they want to wait until they've reformed the House of Lords, but we need to chip away at them now.

"Hunting with hounds is cruel and opposed by 80% of the population, so their wishes should be followed.

"We've had rallies before, which several hundred people have attended and we're expecting more this time."

MP Mike Foster was forced to drop his Private Member's Bill bringing in a ban after opponents talked it out in the Commons in March.

He had won huge support from anti-hunt protesters, such as the League Against Cruel Sports, but had also been opposed by pro-hunt lobbyists, who organised a Countryside Alliance rally to Hyde Park, which attracted 250,000 people.