Britain's exit from the European Union may be "unstoppable", Alistair Darling has warned.
The former Labour chancellor, who ran the successful Better Together campaign to keep Scotland part of the United Kingdom, said on Tuesday there were striking similarities between the independence referendum and the debate about the EU.
Writing in The Guardian, he said: "It’s not easy to win a referendum. I know. You need to be absolutely clear about not just the question but also who and what you are fighting against. As we drift – and drifting is what we are doing – towards another referendum, this time on Europe, there is a real risk the fight will be lost before it begins.
"The daily drumbeat of negative claims about the EU is creating a momentum towards exit that may become unstoppable. Regardless of whether a referendum actually happens, those who support Britain’s continued membership must start now to recover the ground lost so far."
Darling said there was a "powerful case" to be made for the UK remaining a part of the EU, but it needed to be made with "vigour". He warned that if it was not, anti-EU campaigners would be able to exploit unhappiness with the status-quo. "Ukip and the SNP are two sides of the same coin," he said.
David Cameron has promised to hold an in/out referendum in 2017 should he win the next general election. While Ed Miliband has said Labour would only give the public a vote if any more powers were transferred to Brussels.
Last night Germany's deputy finance minister Steffen Kampeter has said he wants the UK to remain in the European Union, adding that the EU will “find ways to offer Britain a good chance to stay in".
Speaking to Newsnight on Monday, Kampeter argued that Britain "opting out" would be a “catastrophe”.
“We are not alone in stating that the Brits should stay in – [Italian Prime Minister] Matteo Renzi stated yesterday it would be a catastrophe [if Britain left]," Kampeter told Evan Davis. “We want them [Britain] in and we will find ways to offer Britain a good chance to stay in. And please do not forget opting out is not economically very preferable to the United Kingdom and has many disadvantages.”