General Election 2015: Ex-Tory candidate defects to Ukip in 'hammer blow' for David Cameron

But Conservative party says Mike Whitehead was sacked from standing in the Hull West and Hessle seat last week

Nigel Farage said it was a 'hammer blow' for the Conservatives (Getty)

The election campaign is only a week old but we have already seen a defection after a Conservative parliamentary candidate jumped ship to Ukip this morning.

Mike Whitehead, who was standing in the Hull West and Hessle seat for the Conservatives, is also an East Riding councillor.

He said he decided to leave the party because he was "disgusted" with the behaviour of the ruling Tory group in East Yorkshire and the "wilful refusal" of the Conservative central office to intervene. He insisted the "secretive" council needed to be "opened up" and be made more transparent.

Nigel Farage hailed the defection as "another hammer blow" to the Conservative party's hopes of making gains in the north of England.

Douglas Carswell became the first Conservative MP to defect to Ukip last summer (Rex Features)

But the Tories hit back, releasing a statement claiming he was sacked from the party last week because he refused to support the local Conservative council candidate.

"We wrote to him last week to say that his position was untenable and he could not stand for us at the general election," the statement said.

"We were already selecting a new candidate for this constituency. This is typical Ukip - cynical, misleading and utterly calculating to try and score political points."

Mr Whitehead still featured as a Conservative candidate on the Hull Conservatives website until this morning however:

Mike Whitehead still features on the Hull Conservatives website as their candidate (Hull Conservatives)

And he was also listed on the official national Conservative party website this morning. He has now been removed from both. A spokesman for the party said the delay in removing him from the websites was due to the Bank Holiday weekend.

The constituency is a safe seat held by Labour's former Cabinet minister Alan Johnson, who was approached by senior members of the Labour party last autumn about the prospect of taking over from Ed Miliband as leader.

Shadow minister Jon Trickett claimed it showed the Tories "increasingly share the same people as well as the same policies".

"Both stand for increased health service privatisation, extreme spending plans which threaten the NHS and further tax breaks for those at the top," he said.

“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."

Explaining his reasons for joining Ukip, Mr Whitehad said: “I believe as a member of UKIP, I will be able to speak up for the residents and represent their views on the Council. I also hope that with the election of other UKIP Councillors, I can help open this secretive Council up and make it more transparent and work better for the residents rather than to the benefit of the few.

Mr Farage said: "I am delighted to be welcoming Mike to the party at this exciting time. His move to UKIP just underlines that today, the real party of opposition to Labour in the North Is UKIP. It is another hammer blow to Tory pretensions in the north of England."