Former Europe Minister Keith Vaz has added his voice to those calling for a referendum on the new EU treaty.
Keith Vaz says the British people should have a chance to vote
He told the BBC it was time for British people to be allowed to decide the UK's place in Europe "once and for all".
The referendum could be held on the same day as the next general election, the Labour MP for Leicester East said.
Critics say the treaty is almost the same as the discarded EU constitution, on which a referendum was promised, but ministers say this is not true.
Mr Vaz told BBC Radio 4's Today programme: "We should not be afraid of actually putting this argument before the British people.
"We don't need a referendum on the reformed treaty because we didn't have one on the Nice Treaty or on Maastricht. But I think there's a difference between need and desirability.
"And I think once and for all we need to put this behind us by putting it to the British people.
"And I am absolutely convinced that we will win any test of public opinion as to whether or not the British people want us in Europe, at the heart of Europe, which is what's happened over the last 10 years, or whether they want us to turn our back on Europe."
The Tories, UKIP and the GMB and RMT unions have called for a referendum.
Shadow foreign secretary William Hague said:"Keith Vaz is absolutely right to come forward and demand a referendum on the new EU Treaty.
"Gordon Brown's intellectual case against letting the British people have their say is now clearly collapsing."
He added: "But Vaz is wrong to try to wrap up the referendum on the renamed EU Constitution with a trick question on 'EU - in or out?'.
"As the French and Dutch voters showed when they rejected the original constitution [in 2005], that is not the issue."
Ian Davidson, a Labour MP spearheading a campaign for a UK referendum on the treaty, has said he could gain the support of up to 120 Labour MPs.
But Foreign Secretary David Miliband said the constitution had been "abandoned" and MPs would see the new treaty was in the UK's best interests.
Europe Minister Jim Murphy told BBC Radio 4's World at One: "We have made it clear that, because of the real changes, both in form, substance and style, and the abandonment of the constitution, therefore we have moved away from that previous situation that we had and we now have a treaty which is in line with previous treaties.
"And we didn't have a referendum of any form, whether specifically on a treaty or on our membership, on any of these previous treaties under Baroness Thatcher, John Major or Tony Blair."
UK Independence Party leader Nigel Farage said: "I am very glad that he [Mr Vaz] has seen sense and realised that there is no way the government can avoid letting the people have their say on such an important issue, especially since the European Parliament have admitted that this is the Constitutional Treaty.
"If his suggestions of a vote on the same day as a general election are taken up, we could also be faced with the unusual situation of our three main parties having to talk about Europe on the campaign trail, instead of pushing it under the carpet."