Britain's traditionally pro-European junior coalition party said on Friday that a referendum on the country's membership in the European Union should take place if there was a "material change" in relations with Brussels.
Speaking ahead of a Liberal Democratic conference in Glasgow, manifesto author and aide to the party leader David Laws said the party would hold a full in-or-out referendum if Britain's relationship with the EU changed.
"We've made it clear that it's our manifesto position," he told The Times newspaper.
"It's the debate we are having at conference, that if there is a material change in the next Parliament we would have a referendum, which is basically whether Britain is in or out of the European Union."
Prime Minister David Cameron, leader of the Conservatives who are the senior party in the coalition government, promised to renegotiate the terms of British membership of the 28-member bloc and hold a referendum if he is returned to power following polls due in 2015.
Laws said that the majority of EU countries want to see a more devolved EU and that most of his party members support the repatriation of some powers to Britain.
His comments strike a different tone from his leader and Deputy Prime Minister Nick Clegg who slammed Cameron's referendum plans when they were announced in January.