Launching Stars and Strife, a book about the EU's relationship with America, John Redwood led calls for Britain to "play its strongest hand" and threaten to end payments to other countries unless Britain is allowed to opt out of EU policies on defence, borders and currency.

Redwood stopped short of calling on the ideas to be adopted as official policy, he said he was taking the party's current policy of renegotiation "a bit further and thinking it through".

The event was supported by shadow defence secretary, Iain Duncan Smith, and David Davis, chairman of the Public Accounts Committee, says the Times.