The Staggers 6 June 2015 Labour's next split: the referendum Labour may soon find itself just as riven by Europe as the Conservative Party. The face of Labour's In campaign? Photo: Getty Images Sign UpGet the New Statesman's Morning Call email. Sign-up Chuka Umunna has called on Labour to be part of a "broad, grassroots campaign" to keep Britain in the European Union, warning that a narrow campaign would see the party and the In campaign cast as "a cosy club of established political parties and big businessess". The remarks come after Alistair Darling, the former Labour Chancellor and head of Better Together, the cross-party campaign to keep Scotland in the United Kingdom, slapped down Andy Burnham's suggestion that the cross-party campaign for the Union was responsible for Scottish Labour's travails. "That explanation doesn’t explain why we were trounced in 2011 or why we lost in 2007," Darling tells the Times, "The Scottish Labour party’s problems are greater than that. Never forget we won the referendum.” Labour's shadow business secretary and former leadership candidate set out his ideas for how the referendum campaign should be fought and won in an interview with Progress magazine. He also shed further light on why he - along with his campaign lieutenants - opted to endorse Liz Kendall's campaign for the leadership. "She has asked all the questions, she has made the arguments that I would have made if I was still in the contest," Umunna said. The MP for Streatham believes that the "three challenges" Labour must tackle are: "how do you deliver good public services in a fiscally cold climate; secondly, how do you harness all of the energy that technological change is bringing to create opportunities when that technology is destroying jobs people have done for generations; and thirdly, how do we pay our way in the world?" Kendall, Umunna, believes, "has started to map out the answers in a fearless way, a courageous way." But it is the question of Europe and how to respond to it that may come to dominate Labour's thinking over the coming months. › Labour deputy leadership candidate Caroline Flint unveils another 12 supporters Stephen Bush is political editor of the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!