The Draft Lisbon Treaty Referendum Bill revealed.

William Hague, the Shadow Foreign Secretary:

"Gordon Brown promised the British people a referendum on the EU Constitution. The Lisbon Treaty is in effect the EU Constitution under another name, so Brown’s attempt to deny his referendum promise amounts to a calculated act of political dishonesty"

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The Conervatives have also released a draft Referendum Bill for consultation; it will set out plans to ask the public, in a referendum:

""Should the United Kingdom approve the Lisbon Treaty?" The answer will be a simple ‘yes’ or ‘no’.""

If the electorate voted ‘no’, then the European Union Amendment Act 2008 (by which the Lisbon Treaty was approved) would be suspended and repealed.
The draft Bill and Hague's full comments may be read here.

Hague goes onto say that every "vote for the Conservatives on Thursday is a vote to increase the pressure on Gordon Brown to honour his word and grant the British people their rightful say on this Treaty".

Another fact relating to the Lisbon Treaty is the one delivered by Jim Nicholson, the Conservatives and Unionist candidate in Northern Ireland:

"Only the Conservatives and Unionists can deliver to the people of the UK a referendum on the Lisbon Treaty. On 4th June, I urge the people of Northern Ireland to make their voice heard and demand a referendum on Lisbon - by voting Jim Nicholson 1."