Liberal Democrat MEP Sir Graham Watson has described Liam Fox's speech about the future direction of the European Union as "a desperate move by a discredited Tory to bang the populist drum to try to revitalise an ailing political career".
Sir Graham said:
"Large economies are making sacrifices in order to keep the eurozone together and sort out the colossal debt crisis.
If Tories honestly believe that we will simply be allowed to renegotiate our membership at the 11th hour without damaging jobs, trade and our rebate then clearly they are deluded.
"So I call on the Conservatives to get real, stop pandering to the right just to keep traditional supporters happy in the short term and get back to the job of securing Britain's long-term prosperity."
Former defence secretary Liam Fox has said that the UK should leave the European Union unless there is a rebalancing of their relationship.
Foreign Secretary Hague said there would be a "very, very powerful" case for a referendum if Europe moved towards a more federal system.