Labour's promises on an EU referendum
"We will put it — the EU Constitution — to the British people in a referendum and campaign whole-heartedly for a 'Yes' vote." — Labour Party manifesto, May 2005
"The manifesto is what we put to the public. We've got to honour that manifesto." — Gordon Brown, BBC 1 Politics Show, June 24, 2007

So stop trying to put it all down as a plot by UKIP and the Conservatives.