'It would be a fatal mistake:' Kenneth Clarke warns Britain against leaving EU

Kenneth Clarke tonight warned that it would be a “fatal mistake” for Britain to leave the European Union as he cast doubt on whether the referendum promised by David Cameron would take place.

The Minister Without Portfolio and leading pro-European Conservative urged the Prime Minister to be “positive” in his negotiations with the EU, saying that would secure a better deal for the UK.

In his first public comments since Mr Cameron announced an in/out referendum by the end of 2017 if he wins the next election, Mr Clarke declared: “It is in our vital national interest that we avoid the fatal mistake that would be a No vote if a referendum is held in the next few years.” His use of the word “if” suggests that he believes the talks on a new EU treaty may take longer than the Prime Minister envisages - a view shared by several other EU nations.

Speaking at the launch of a new cross-party group, the Centre for British Influence, Mr Clarke vowed that Tory pro-Europeans would mount a long overdue fightback. “The case has not been made properly for British membership of the EU for many years. The time has obviously now come for us to put the case more strongly and more coherently,” he said.

Mr Clarke, who will help Mr Cameron try to win a new EU-USA trade deal, praised Margaret Thatcher’s “bold and positive” approach in creating the European single market. “There is a huge potential prize out there for the UK if only we focus our attention and influence in any future negotiations on the positive things that really matter. We need to concentrate on what we are in favour of, and not just what we are against,” he said.

Danny Alexander, the Liberal Democrat Chief Treasury Secretary, told the group’s launch reception: “It should be obvious to all that we are more powerful negotiating from inside Europe than from the sidelines…The idea that we should extract ourselves from the bulk of EU obligations is nonsensical.”

Lord Mandelson, Labour’s former Business Secretary and a former European Commissioner, said Eurosceptics had “been allowed to get away with murder” through lies and false propaganda. “The pro-Europeans have bided our time. Now we must unbide our time,” he said.

Peter Wilding, the centre’s director, said: “Many British people think their country is powerless in Europe. This is fundamentally wrong and unpatriotic. Britain helped create modern Europe, our allies want us in and it is time we finished the job.”

William Hague, the Foreign Secretary, told a Commons debate on Europe: “British membership of a reformed competitive EU is strongly in our national interest.It's our responsibility as one of the leading members of the EU to press for reforms that must happen if the EU is to succeed in this century; more competitiveness, flexibility, democratic accountability and fairness for countries both in the eurozone and outside it. All those will benefit the UK and the EU as a whole.“