Ukip leader Nigel Farage has insisted that his German wife does not want the vote – at least in a referendum on Britain’s membership of the European Union.

Mr Farage has just published a book, The Purple Revolution, that makes clear that a “red line” in any coalition deal with the Conservatives would be the terms of David Cameron’s planned ‘in/out’ referendum in 2017. He wants to ensure that EU citizens living in the UK who do not hold British passports, including his wife, are not allowed to vote in this plebiscite.

Talking to The Independent on Sunday as part of a tour of the Ukip-held Rochester & Strood constituency in Kent, Mr Farage clarified that his wife agreed with his view: “Do I think my wife, a German passport holder, should be allowed to vote in this referendum? No I don’t – nor does she, by the way.”

Mr Farage was speaking before he announced the defections of local councillors from the Conservatives to Ukip. The constituency’s MP, Mark Reckless, switched to Ukip last year and won the resulting by-election under his new purple-and-yellow colours with a majority of just under 3,000.

Mr Farage is standing for Parliament in another Kent seat, South Thanet, and is the bookies’ favourite to win.