The Tory peer, and David Cameron's adviser on growth, said offering a referendum on EU membership would be a "punt" that would "drive away inward investment".

BBC: Eric Pickles

Their intervention was welcomed by the Labour peer Lord Morris of Manchester - the parliamentary adviser to the Royal British Legion and a long-time campaigner on behalf of the Gulf veterans.

BBC: NEWS | UK | England | Bishops call for Gulf War payouts

Conservative peer Lord Blackwell, who was a political adviser to former Prime Minister John Major, said that "the primary reason for our current deficit" was a growth in public spending from 40% of GDP to closer to 50% over the last decade.

BBC: Minister: Government 'on track' to cut deficit

Lord Hill, who was political secretary to John Major in the 1990s and a special adviser to Ken Clarke in the 1980s, was made a peer and became an education minister after the coalition came to power in May 2010.

BBC: Lord Strathclyde resigns from cabinet