Differences are arising within the Labour party on how to fight for the UK to remain in the EU.
Liz Kendall and Andy Burnham, two of the frontrunners in the Labour leadership contest, disagreed on how best to tackle the issue in their first hustings.
Kendall, who is considered the most Blairite of the contenders, said it would be a “profound mistake” for the party to “somehow boycott” the “yes campaign” to stay in the EU.
Andy Burnham, meanwhile, has argued in favour of a separate pro-EU strategy for the Labour party, running parallel to the “yes campaign”.
Burnham, who is considered the favourite to become leader in September, recently said he had “learned the lessons" from the Better Together campaign for Scotland to remain in the UK. He said voters were put off by how closely Labour had worked with the Conservatives for a continued union.
Some key Labour figures are leaning heavily in favour of Kendall's outlook – former chancellor Alistair Darling said it would be a “massive mistake” to not adopt the standard yes campaign.
Prime Minister David Cameron has promised an in-out referendum on membership before the end of 2017, but first is trying to renegotiate Britain's membership with the bloc.