DAVID Cameron blamed "deep disillusionment" with the EU for Ukip's stunning poll victory - but again dismissed the prospect of an electoral pact with the party.
The Prime Minister said the message from the public was "received and understood" after Nigel Farage's party topped the European parliament ballot.
But he insisted voters will back the Tories next year when they are confronted with a choice between himself in Number 10 or Labour leader Ed Miliband.
"People are deeply disillusioned with the European Union," Mr Cameron told BBC Radio 4's Today programme. "They do not think the current relationships are working well enough for Britain.
"They want change and as far as I am concerned that message is completely received and understood."
Mr Cameron said only the Conservatives were offering the realistic prospect of an in-out referendum, after renegotiating links with the EU.
"We don't do pacts and deals. Conservative candidates will stand as Conservatives, fight as Conservatives and I hope win as Conservatives," he said.
"We are not going to be doing deals and pacts."
But the premier ducked the question of what disciplinary action would be taken against Tory candidates who struck local arrangements with Ukip, saying only: "I don't see any prospect of this happening.
"From what I read in the Sunday newspapers, Nigel Farage wants to destroy the Conservative Party, not work in tandem with it.
"I think there's a great myth that there's somehow some great pact or deal to be done.
"If you want a referendum on Europe, if that's the most important thing for you, there is only one party and one potential prime minister that can deliver that and that is the Conservatives in government. Labour and Liberal Democrats don't want that referendum, Ukip can't deliver it."
Mr Cameron refused to discuss whether he would opt to form a coalition with Liberal Democrats or Ukip if the next election results in a hung Parliament.
"I'm going to be very strict on this one," he told Today. "Between now and the next election, I'm only going to be talking about my goal, which is all-out Conservative victory, and I believe that is achievable."
He dismissed Mr Farage's anti-politics image as "a normal bloke in the pub", describing him as "a consummate politician" and adding: "We have seen that with his expenses and his wife on the payroll."