Boris Johnson has been chosen as the Tory candidate for the 2008 London mayoral contest, but his campaign has run into immediate controversy.

Mr Johnson, an MP and television personality, said that he was looking forward to the challenge and that the days of "King Newt" - a reference to Ken Livingstone, the current mayor and celebrated newt-fancier - were numbered.

As news of his selection was released by the Conservative Party this morning, however, he faced criticism from leaders of the black community for his previous references to black people as “piccaninnies” and Africans having “water melon smiles”.

Responding to his selection, Mr Johnson said: "Across London I’ve met people fed up with paying so much to city hall and getting so little in return.

"The job of the Mayor is simple - to get people to work on time, to ensure people feel safe on the streets, to help people find a place to call home, to celebrate our diversity and to champion our success.

“My determination to lead this city is stronger than ever. After seeing both the good and bad that London has to offer, I am committed to making London greater and standing up for every Londoner that invests so heavily in our city."

In a statement issued this morning David Cameron, the Tory leader, said: “Boris will be an excellent candidate and I know the party will unite behind him to remove Ken Livingstone from office. It’s about time that all Londoners had the chance to vote for real change.”

The US-style open primary allowed London voters who were not members of the Conservative Party to take part, by registering using a premium-rate phone line.

Caroline Spelman, the Conservative party chairman, said that the move was “a first for British politics”. She said: “Running a London-wide open primary is a first in British politics. By opening up the process and running open hustings we have given all Londoners the chance to vote on the Conservative appointment and influence the outcome."

Mr Johnson got 15,661 votes, way ahead of his nearest rival Victoria Borwick who got 1,869 votes.

Less than an hour after his selection he was facing his first hurdle, as it emerged that Lord Ouseley, the former head of the Commission for Racial Equality, Michael Eboda, the editor of the New Nation newspaper, and Steve Pope, editor of The Voice, had immediately written to Mr Cameron urging him to disown Mr Johnson’s “offensive, insulting and abusive” comments.

They also objected to Mr Johnson’s description of Nelson Mandela’s South Africa as “majority tyranny of black rule”.

They wrote: “As Boris Johnson is now the official Conservative candidate for the forthcoming elections for the Mayor of London, we write to request that you clearly dissociate yourself personally and your party from his offensive comments that are an inescapable barrier between your party and the black communities in this country.

“You will be aware that there has been much discussion and a growing level of serious concern expressed within London’s Caribbean and African communities in relation to this series of offensive statements made by Mr Johnson.

“Since he declared his candidacy, the Conservative Party has remained silent on this matter but there is now no reason for you not to clearly dissociate your party from his statements as he is now your official candidate.

“The issue goes beyond the London election - it strikes at the heart of the Conservative party’s stated claim to be open to all.”

Mr Livingstone also lined up to criticise Mr Johnson, accusing him of lacking managerial competence or political consistency.

“He opposed congestion charging and did a U-turn on this, supported the anti-lesbian and gay Section 28 and then abandoned this, says he is green but opposed the Kyoto treaty," said Mr Livingstone.

“In addition to damaging mistakes he has made policy on the hoof, proposing a totally wrong system of bus contracts for London and coming out against the requirement that 50 per cent of new housing should be affordable.

“London is currently the world’s most successful city and requires serious city administration, not a shambles.”

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