The Business Secretary Vince Cable has said that it is not sensible to deal with UKIP by "insulting" or "ignoring" them.
He told Sky News' Murnaghan programme: "I think it's very important that UKIP are subject to the kind of scrutiny that we are subjected to and other major parties.
"It's absolutely right, I have never believed that it's sensible to deal with Ukip by insulting them or ignoring them.
"They are a force at the moment and they should be subject to scrutiny and subject to debate, let's try and find out what their policies are, it isn't terribly clear."
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