David Cameron must go out and make the case for Britain's continued membership of the European Union, one of the grandees of the Conservative Party has warned.
Lord Howe of Aberavon, who served as chancellor and foreign secretary in Margaret Thatcher's government, said the Prime Minister had made his position more difficult by his "repeated concessions" to the Eurosceptics.
He said that Mr Cameron now must give a lead on the issue.
Mr Cameron is currently committed to renegotiating the terms of Britain's membership and then putting the outcome to a vote in an in/out referendum after the next general election if the Conservatives win power.
While the Prime Minister has said he wants Britain to remain in the EU, Lord Howe – whose resignation over Europe in 1990 triggered Baroness Thatcher's downfall as prime minister – said that it was not enough.
In a statement released by the pro-EU British Influence campaign, Lord Howe said: "The more people understand and experience the reality of Britain's place in today's interdependent world the less likely they are to want this country to leave the EU.
"Sadly, by repeated concessions to the Eurosceptics, the Government made its own position on Europe more difficult. Now the Prime Minister and his ministers need to make the case for membership strongly and clearly, rather than just leaving it to President Obama, Nissan and the CBI – powerful as these may be."
At the same time, British Influence released a YouGov poll of more than 700 "opinion formers" showing 69% believed Britain should stay in the EU as against 23% who wanted to leave.