David Cameron takes aim at Ukip as poll shows boost in wake of Maria Miller expenses scandal

The Prime Minister has changed tack as he opened the Conservatives’ campaign for next month’s European Parliament elections (Getty Images)

David Cameron launched a rare direct attack on the UK Independence Party as an opinion poll suggested that Nigel Farage’s party had reaped a reward from the controversy over Maria Miller’s expenses.

The Prime Minister, who has normally ignored Ukip in the past to avoid giving it the oxygen of publicity, changed tack as he opened the Conservatives’ campaign for next month’s European Parliament elections. The anti-EU party is tipped to come first or second, pushing the Tories into a humiliating third place.

An Ipsos MORI survey put Ukip on 15 per cent, its joint highest rating after a rise of four points since last month. Labour (37 per cent) enjoyed a six-point lead over the Tories (31 per cent).

The poll found that last month’s Budget was the most popular by a Tory Chancellor since 1987 and that more people are satisfied with George Osborne’s performance than dissatisfied. But the mini-boost from the Budget appears to have been halted by the controversy which led to Ms Miller’s resignation as Culture Secretary on Wednesday.

In a speech in Washington on Friday, Mr Osborne will paint an upbeat picture for the UK and other western nations as he tries to shift the political spotlight back to the economy. He will say: “The pessimists are on the march again with their predictions of stagnation. We, the optimists, can prove them wrong again. Our nations' best days lie ahead."

Arguing that the Government has won the economic argument against Labour, the Chancellor will say that the UK economy shows that “fiscal consolidation and economic recovery go together, and undermines the pessimistic prognosis that only further fiscal stimulus can drive sustainable growth. Indeed that is precisely the wrong prescription for our economies.”

Speaking in Manchester on Thursday, Mr Cameron branded Ukip “extremists" who would not stand up for Britain's interests in Brussels. He insisted that public "apathy", rather than a rival party, was his main fear in the Euro elections.

The Prime Minister claimed the Tories were the only party with a clear plan – to "renegotiate, get the best deal for Britain, then put the decision to the British people" in a referendum. He argued that the other parties were in “two extremist camps." He said: "One [the Liberal Democrats and Labour] says ‘we love the EU.’ The other [Ukip] says ‘we hate the EU.’ One says 'we want things to stay the same'. The other says 'let's just walk away from the EU'.” He claimed only the Tories would stand up for “Britain’s national interest.”

Mr Cameron said: "When it comes to standing up for Britain in Europe, is there anyone you would trust less than a group of Ukip MEPs? They talk the talk in Britain - but as soon as they're on that plane to Brussels they change completely. When they do actually bother to vote, they don't stand up for Britain.”

The Ipsos MORI poll made grim reading for the Liberal Democrats. They are down four points to nine per cent after Nick Clegg’s two broadcast debates with Mr Farage, mirroring Ukip’s four-point rise.

The finding will increase fears among some Lib Dems that Mr Clegg made a strategic error by challenging Mr Farage to the debates. “It was a desperate move because Nick had his back to the wall but now we are in a worse place,” one internal critic said.

But Clegg allies hope the Lib Dem leader’s higher public profile will woo some pro-European voters and prevent a predicted wipeout in which the party loses all it 12 seats in the European Parliament.

Mr Farage’s personal ratings have risen since the debates. Some 40 per cent of people are satisfied with the Ukip leader’s performance and 36 per cent dissatisfied, giving him a net rating of +4, up from -10 last month. Mr Clegg’s score remained steady, with 29 per cent satisfied and 63 per cent dissatisfied, a net rating of -34. Mr Cameron’s net rating is -18 while Ed Miliband is on -21.