The leader of Ukip Paul Nuttall has backed his immigration spokesman after he re-tweeted a slogan mired in racist controversy.

John Bickley, who is also the party's treasurer, re-tweeted a cartoon with the words "If you want a jihadi for a neighbour - vote Labour" to his 4,400 followers.

Mr Bickley, a member of Ukip's national executive committee, has since deleted the tweet and, according to Mr Nuttall, has apologised.

The party leader, speaking at his by-election campaign office in Stoke-on-Trent on Monday, said Mr Bickley had been unaware of the contentious roots of the slogan.

Other Twitter users, critical of the Ukip spokesman, re-posted Mr Bickley's retweet alongside a version of a campaign leaflet from the 1964 Smethwick general election, issued in support of the Conservative Party's ultimately successful candidate Peter Griffiths.

The original campaign slogan in the Midlands constituency used a racist term, substituted for the word "jihadi" in the version Mr Bickley re-tweeted.

Mr Nuttall, backing his immigration spokesman, said: "He's got my support, absolutely, he's apologised for it."

He added: "It wasn't clever and John's apologised and he's taken it down."

Mr Nuttall, who is battling to secure the Labour-held Stoke Central constituency in a by-election vote on February 23, said Mr Bickley had been "mortified".

The party leader said: "He's not a politics anorak, John, and I don't think he understood the history of that slogan which goes back to the 1960s.

"That was pointed out to him and as soon as it was, he was mortified by it and he took it down and he's apologised."