A former Labour Party activist is taking the Government to court today over its refusal to grant a referendum on the European Union Lisbon Treaty.

UK Independence Party (Ukip) parliamentary hopeful Stuart Bower is bringing a claim against Gordon Brown, accusing the Government of a breach of contract.

Mr Bower, a former police officer, argues that the Lisbon Treaty, signed by the 27 member states of the EU in December, is effectively the same as the European Constitution, on which the Government promised a referendum before the last general election.

Brighton County Court will be asked whether the Government's refusal to hold a referendum amounts to a breach of contract with Labour voters at the 2005 General Election, he said.

The legal challenge comes amid lengthy debate about the Treaty in the Commons ahead of its expected ratification by Parliament.

Mr Bower, Ukip's prospective parliamentary candidate for Hove in East Sussex, said: "From the papers I have been sent, it seems that the Prime Minister is denying the pledge made in his Government's manifesto.

"Surely this is a desperate act as everybody knows the commitment was made and that is why many people gave their votes to his party.

"To me, it is a clear case of breach of contract. They made a written promise and broke it. That was a contract between the Government and the people."

The Lisbon Treaty will formally define what the EU can and cannot do, and what means it can use, amending existing EU treaties.

All main parties promised a referendum on the constitution in their election manifestos, but the Government argues that the Lisbon Treaty does not have the same significance.

Mr Brown argues that no referendum is needed because the Lisbon Treaty does not have the constitutional character of the document rejected by French and Dutch voters in 2005.

The hearing takes place at Brighton County Court from 10.30am.