PRIME Minister David Cameron was dealt “another huge blow” yesterday when a Conservative election candidate announced he would stand for Ukip.

Hull West and Hessle candidate Mike Whitehead, a councillor on East Riding Council, said he defected after being left “disgusted” by the behaviour of the council’s ruling Tory group.

He said that he had become increasingly worried since 2011, when seven Conservative councillors from Haltemprice and Howden resigned, citing bullying and intimidation.

“In my opinion, the behaviour of the ruling group has only gotten worse since then,” Mr Whitehead said.

“Now, that same group have managed to gain control of the local party structures by ensuring they are responsible for the organisation of the local election campaign.

“However, the Conservative Party at national level has declined to get involved in what it sees as a remote internal squabble out in the shires.”

Mr Whitehead also feels that he would better be able to speak up for residents and represent their views on the council as a member of Ukip.

The Conservatives claim that Mr Whitehead did not defect since he was sacked from the party last week for refusing to support a local Tory council candidate.

“We were already selecting a new candidate,” a spokesman said.

But Labour shadow minister without portfolio Jon Trickett said: “This is another huge blow for David ­Cameron’s authority. Even his ­candidates know he cannot win a majority.”

And he added: “David Cameron will not rule out working with Ukip, but this is clearly what his party wants. David Cameron must now come clean and tell us what his plans are to do a deal with Nigel Farage and Ukip.”

Ukip leader Mr Farage said he was “delighted” to welcome Mr Whitehead to the party, calling his defection “another hammer blow to Tory pretensions in the north of England.”

He claimed it underlined Ukip’s status as the real party of opposition to Labour in the north.

Hull West and Hessle is safe Labour territory. Former home secretary Alan Johnson is defending a 5,700 majority from the 2010 general election, when the Conservatives finished third.