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.

'Convinced'

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.

Ian Davidson, a Labour MP spearheading a campaign for a referendum, has told BBC News he believes 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.

See also:

EU referendum pressure on Brown

Reuters: Aug 31, 2007
By Adrian Croft

LONDON - Prime Minister Gordon Brown came under renewed pressure to call a referendum on a European Union treaty on Friday when a former minister proposed asking voters if Britain should stay in the EU.

Unlike many of those calling for a referendum, Keith Vaz, a member of parliament for Brown's own Labour Party and one-time Europe minister, is pro-EU.

He sees a broader referendum as a way of stopping constant sniping by Eurosceptics at Britain's membership of the EU.

The Conservatives and some Labour MPs want Brown to hold a referendum on a proposed new EU treaty, saying it is little different from a defunct EU constitution which the government pledged to put to a popular vote.

The original treaty to establish a constitution for the EU was signed by member states in 2004 but never ratified after French and Dutch voters rejected it in national referendums.

Brown argues the successor treaty is much less far-reaching than the constitution and can be ratified by parliament as previous treaties have been.

Opponents of the treaty argue that it hands too much power to Brussels.

The debate creates a thorny problem for Brown, who succeeded Tony Blair as prime minister in June. Political analysts think there is a good chance British voters would reject the treaty, undermining Brown's authority and posing a headache for the EU.

"We don't need a referendum on the reform treaty ... but ... once and for all we need to put this behind us by putting it to the British people," Vaz said.

"I'm absolutely convinced that we will win any test of public opinion as to whether or not the British people want us in Europe," he told BBC radio.

SETTLING EU QUESTION

In an open letter to the Sun newspaper, Vaz said a referendum would "settle the Europe question for a generation."

He said a referendum should be held on the same day as Britain's next general election -- which Brown does not have to call until 2010 but which commentators believe could be held as early as this year.

The question Vaz would put to voters is: "Do you support Britain's continuing membership of the EU as set out under the terms of the reform treaty?"

Labour legislator Graham Stringer, a treaty opponent, said Vaz was proposing a broader referendum because pro-Europeans thought it would be easier to win a vote on British membership of the EU than on the treaty.

Stringer told the BBC he believed a majority of members of parliament favoured a referendum, opening the prospect parliament could force the government to hold a popular vote.

Conservative foreign affairs spokesman William Hague praised Vaz for calling for a referendum but said he was wrong to wrap it up with a "trick question" on Britain's EU membership.

Ministers repeated there was no need for a referendum.

The row over the referendum, together with the strong poll lead Brown has opened over the Conservatives, has fuelled speculation Brown could call a general election as early as October to seek popular backing for his stance.

A YouGov poll in Friday's Daily Telegraph showed Labour with an eight-point lead over the Conservatives, enough to give Brown a crushing 100-seat parliamentary majority at a general election.