By Jason Groves for the Daily Mail Ukip last night warned they will target Boris Johnson over his support for a migrant amnesty if the Conservatives try to use him to erode their support. Tory sources yesterday confirmed that the London Mayor will be deployed as a ‘Ukip killer’ in next year’s general election, following confirmation that he wants to return to parliament. Mr Johnson has agreed to carry out a tour of key marginal seats, where Conservative strategists believe he may be able to persuade traditional voters who have defected to Ukip to return to the Tory fold. Nigel Farage, right, has warned the Conservative Party that he will target Boris Johnson over migrant amnesty
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Tories plan to use Boris Johnson as a 'Ukip killer' during the 2015 election
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Nigel Farage plans to counter that threat by raising the migration issue
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The Ukip leader believes the current London mayor is soft on immigration
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