Paul Nuttall, UKIP's deputy leader, says any election pact with the Conservatives would be "very difficult" while David Cameron heads up the party.
"You really can't believe a word he says on the European Union and he's also a guy who called us closet racists," he said.
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The abusive pasts of more than 1,300 violent partners have been disclosed under a scheme introduced less than a year ago, new figures show.
David Cameron has said he wants to cut taxes after the next election because British people "deserve a reward" following years of austerity.
The number of pothole compensation claims is rising and campaigners have urged the Government to pledge more money to fix Britain's roads.