David Cameron's “vague” promise of a renegotiation of Britain's membership of the European Union will damage economic growth and distract the Prime Minister's attention from more important issues such as jobs, immigration and crime, Nick Clegg warned today.
The Liberal Democrat Deputy Prime Minister made clear the depth of division between the coalition parties over Europe, saying that Mr Cameron had announced a five-year timetable for the "so-called" renegotiation and an in/out referendum on UK membership "for his own political purposes".
But he indicated that the referendum promise would not necessarily prevent Liberal Democrats entering into a renewed coalition with Conservatives in the case of a hung Parliament after the 2015 general election.
The Prime Minister was boosted today by a letter signed by 56 leaders of industry and the City, who welcomed his renegotiation proposals as "good for business and good for jobs in Britain".
Signatories to the letter to The Times included London Stock Exchange chief executive Xavier Rolet, Standard Chartered chairman Sir John Peace and Diageo chief executive Paul Walsh.
They challenged Mr Clegg's argument that a protracted renegotiation will be bad for business, saying: "We need a new relationship with the EU, backed by democratic mandate."
And supporters of the plan welcomed German chancellor Angela Merkel's comment that she was "prepared to talk about British wishes... (and) find a fair compromise" as a sign that other European powers will be ready to engage with Mr Cameron's proposals for reform of the EU.
But Mr Clegg told LBC 97.3 radio: "I simply don't understand the point of spending years and years and years tying yourself up in knots, so-called renegotiating the terms of British membership in ways which at the moment at least are completely vague.
"I think that discourages investment and inhibits growth and jobs, which have to remain our absolute priority at a time when the economy is still struggling to recover...
"The things people worry about are immigration, jobs, crime on their streets. My worry is how are we going to address those concerns, which are the things people care about most, if you are going to spend the next five years touring European capitals coming up with ever more complex ways of renegotiating the status of Britain in the European Union?
"That seems to me to be not actually addressing the things that people care about most in their everyday lives."
Asked if his differences with Mr Cameron over Europe would block a future Tory-Lib Dem coalition, Mr Clegg replied: "I will follow the instructions of the British people.
"If a coalition is necessary following the votes of the British people, then we will play our part. I will always play a responsible role... to ensure this country has good government in the national interest."
Mr Cameron was meeting some of the European leaders face-to-face today for the first time since setting out his EU policy, as he attends in the World Economic Forum in Davos, Switzerland.
His speech to the gathering of political, economic and business leaders focused on Britain's priorities for its 12-month presidency of the G8, including counter-terrorism, tax and transparency.
But he touched on the European question, insisting that his EU policy was "not about turning our backs on Europe - quite the opposite".
He said: "This is about how we make the case for a more competitive, more open and more flexible Europe and how we secure the UK's place in it."
Setting out his case for reform of the EU, Mr Cameron added: "It is not just right for the United Kingdom, it is necessary for Europe.
"Europe is being out-competed, out-invested, out-innovated and it is time we made the EU an engine for growth, not a cause of cost for businesses and complaint for its citizens."
In his long-awaited speech in London yesterday, Mr Cameron said he hoped to persuade all 27 EU states to join in a new treaty to reform the EU for all its members, but was ready to demand a renegotiated status for Britain alone if other nations did not agree.
Draft legislation will be drawn up by the Conservative Party ahead of the election, and will be enacted by the end of 2015 if Tories win to pave the way for renegotiation and referendum within the next two years, he said.
"It is time for the British people to have their say," Mr Cameron said.
"It is time to settle this European question in British politics."
Mr Cameron said a new EU treaty should be driven by the five key principles of competitiveness, flexibility, return of powers to national governments, democratic accountability and fairness.
Crucially, he said it was time for the EU to ditch the universal commitment to "ever closer union" and accept that members can decide for themselves how deeply they want to integrate.