Lord Mandelson on referendum: 'Not what we signed up for'
23 January 2013 Last updated at 09:34 GMT
David Cameron has said there will be a referendum on whether Britain should stay in the European Union, if the Conservatives win the next general election.
The prime minister said he wanted to renegotiate the UK's relationship with the EU, before asking people to vote.
The Labour peer and former European commissioner, Lord Mandelson, said the rest of the EU would not tolerate being treated like a self-service "cafeteria".