More than 30,000 people have signed the Independent’s online petition calling for the Government to introduce a ban on wild animals, ahead of a key vote in the Commons. MPs debate whether to support a ban on performing lions and tigers or back the Coalition’s proposed licensing system at 3pm tomorrow. Tabled by Tory MP Mark Pritchard, LibDem Bob Russell and Labour\'s Jim Fitzpatrick, the backbench debate is a Parliamentary innovation designed to rebalance the relationship between Parliament and the Government. As campaigners continued to lobby MPs ahead of it, the singer Leona Lewis urged supporters to contact their MP to check whether would be supporting a ban. Ms Lewis, a supporter of the World Society for the Protection of Animals, said: “I am shocked and outraged that there needs to be a debate about whether it is okay for wild animals to perform tricks in the big top. I hope that people write to their MP, as I have, to ask them to vote for a ban.”