Boris Slams 'Namby Pamby' Campaign Complaints

Boris Johnson has refused to apologise about negative campaigning by the Conservative party, saying that people should stop being so "namby pamby" about political attacks.

On a day that the Mayor of London was unleashed to try to woo back UKIP voters, he told Sky News that he could not understand when Britain had become so unable to cope with the ferocity of the campaign trail.

Mr Johnson said comparing the SNP in Westminster to a fox in the henhouse was not unfair but a "deeply accurate" representation.

"This is politics. I just can't understand what has happened to us as a country," he said.

"I had someone saying to me that Nicola Sturgeon was deeply offended because I said putting the SNP in charge of running England is like putting Herod in charge of a baby farm. Actually the whole charter of the SNP is to break up Britain."

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The interview took place during a day in which Sky News accompanied Mr Johnson on the campaign trail.

As well as walkabouts in London, the Mayor travelled to Ramsgate, in Kent, to try to win over voters who may be considering backing the UKIP leader Nigel Farage.

His comments on personal attacks will be seen as supportive of the campaign being choreographed by Lynton Crosby, the Australian strategist who has been accused by critics of being too negative.

He also ran Mr Johnson's 2012 campaign against Labour's Ken Livingstone.

Mr Johnson added: "If we've become so namby pamby and sensitive and so offended by a spot of common or garden political imagery then what is happening to us as a nation?" he asked.

He then repeated attacks of the idea of the SNP propping up Labour after the election. But he rejected those who have said the Tory message was putting the union at risk by encouraging Scots to vote SNP.

"The polls are obvious, Labour has given up in Scotland. I keep reading these devastating accounts, they are miles behind.

"They could lose 40 seats. Total massacre. Perhaps more. You could have 50 SNP members of parliament, so the only way you can have a Labour parliament is bolting them on," he said.

He admitted that his own party had to think about how to address the nationalist surge, because it could mean a chance of another referendum that might not be won.

"I think the risk is that you'll have a long and very scratchy, difficult, chaotic period in which Labour is held to ransom by the SNP. Nicola Sturgeon and Alex Salmond wearing the tartan trousers, Scottish tail wagging the English dog.

"I think that will build up such a sense of impatience in the English electorate then there is a real risk of a rupture."

He said that he and Nigel Farage had last spoken years ago, once trying to persuade each other to join their parties.