Britain's main opposition party, Labour, is allegedly looking to offer voters a referendum, on whether the UK should stay part of the European Union, should it win the general election in 2015.

According to a Times Newspaper report, citing an unnamed source, Labour leader Ed Miliband will follow in the Conservative's footsteps and offer to hold an EU membership referendum despite the party being previously highly critical of David Cameron's pledge.

However, Labour has allegedly not set a timeline for when the EU referendum would take place, unlike the Tories which have tabled the vote to be conducted by 2017.

Labour Party official spokespeople had not responded with comment by the time of publication. Labour has also yet to publicly state whether it supports an EU referendum.

UK Chancellor George Osborne has already warned the EU that the UK and other countries will leave the bloc if it does not reform.

He said that if the Conservatives are re-elected in 2015, they will keep their promise to renegotiate the UK's EU ties before offering Britons an in/out membership referendum.

According to a number of recent polls, a slim majority said it would vote to leave the EU if it was given the chance.

"Our determination is clear: to deliver the reform and then let the people decide," said Osborne.

"It is the status quo which condemns the people of Europe to an ongoing economic crisis and continuing decline. And so there is a simple choice for Europe: reform or decline."

"Non-Euro states need their rights legally protected if countries like Britain are to remain in the EU.

"EU treaties are not fit for purpose and [Britain] doesn't want the UK to be forced to choose between joining the euro and leaving the EU."