Tories: Puncture bubble says Tebbit

He urged Tories to ask some "searching questions" about Liberal Democrat leader Nick Clegg's policies.

And he suggested David Cameron had been "shy" about talking up his own proposals "for fear that it would frighten the electors".

Speaking yesterday to BBC Radio 4's World at One, Lord Tebbit urged the Tories "not to hang around because there is a Clegg bubble and the imperative is to puncture the bubble before the 6th of May – the 7th would be too late."

He said there was a "problem" because the Tory campaign was based on research in the marginal constituencies – carried out by the party's deputy chairman and donor Lord Ashcroft – which had found that "one had to appeal to the electors who had voted Lib Dem or New Labour in '97".

He added: "So there's a real problem to get away from that sticky middle ground.

"Now I think the task of the Conservatives is to analyse Mr Clegg's claims and to ask him some searching questions."

These questions could focus on Liberal Democrat proposals for immigration and the euro.