The Secretary of State for Communities has said that the Tory candidate for Mayor of London will “depend on attracting support in second preferences from BNP and UKIP supporters” to win the May 1st election.

Hazel Blears, who is in charge of the Labour party’s local election campaign, made her assertion in an interview with The Sunday Telegraph in which she characterised the council elections as vital for David Cameron.

Labour is braced for considerable losses in the 4,500 seats up for election across England and Wales, with party insiders predicting as many as 250.

The party could lose control of Sheffield to the Liberal Democrats. Lib Dem leader Nick Clegg is an MP for the city.

It is Gordon Brown’s first major electoral test since becoming Prime Minister last year.

In cities such as Birmingham, Manchester, Newcastle and Sunderland, and 73 English district authorities, one third of the council seats are up for election.

Seven English district authorities will elect half of the council while in Wales all councillors in all 22 councils will be elected.

The Prime Minister already faces unrest among his own MPs about plans to extend detention without trial for terrorist suspects and the abolition of the 10p tax band, which took effect last week.

Meanwhile Tory leader David Cameron will be hoping to pick up support in northern England, particularly cities, where his party is currently absent.

“Cameron needs to show he can get real support in the North of England and Wales, beyond his political comfort zone in the shires. Not just a few gains here or there,” said Ms Blears.

Her comments about Conservative candidate for Mayor of London Boris Johnson indicates that the battle for City Hall is set to remain ill-tempered right up until polling day.

“The London Mayoral will be very close, given the resources the Tories are ploughing into the capital,” she told The Sunday Telegraph.

“Success for Boris Johnson will depend on attracting support in second preferences from BNP and UKIP supporters, I am afraid.”

Labour candidate Ken Livingstone, seeking a third term in office, has used the threat of a BNP candidate winning a seat on the 25-member London Assembly as a late theme in his campaign.

“Like all fascist parties the BNP seek power with populist policies but their aim is to divide communities and foster hatred and violence,” he said last week.

“We have to get across one simple fact: there’s only one way to stop the BNP, which is by actually going out to vote against them. A low voter turnout will help the BNP get elected.”

He was speaking after the fascist party had called on its supporters to cast their second preference vote for Mr Johnson – an endorsement he utterly rejected.

“In this race, the Tory clown Johnson is a lesser evil than the Marxist crank Livingstone, so replacing the latter with the former would, on balance, be an improvement for the majority of Londoners,” the party said in a statement on their website.

“Even if Johnson condemns the BNP a second choice vote for him gives you the chance to vote BNP as your first preference and still vote to get Livingstone out of office.”

Ms Blear’s advisers later said she had not mean that Mr Johnson was seeking the votes of BNP members, but he rejected that position.

“Regardless of whether or not she meant to suggest I was deliberately courting BNP votes, this is yet another cynical attempt by Labour to play politics with an issue on which all the mayoral candidates are united,” he said.

“I have said before that I don’t want the second preference vote of any BNP supporter.

“I believe my message of a fresh approach and new ideas for London will resonate with all voters.”

Full list of candidates for Mayor of London:

Richard Barnbrook

British National Party

Gerard Batten

UK Independence Party

Sian Berry

Green Party

Alan Craig

Christian Peoples Alliance and Christian Party

Lindsey German

The Left List

Boris Johnson

Conservative Party

Ken Livingstone

Labour Party

Winston McKenzie

Independent

Matt O’Connor

English Democrats

Brian Paddick

Liberal Democrats