Patrick Mercer, a Conservative front-bencher, has been sacked by his party leader David Cameron after telling Times Online that being called a "black bastard" is part and parcel of being an ethnic minority in the Armed Forces.

Mr Mercer, who was the Tories' Homeland Security Spokesperson and a decorated former Army colonel, had claimed that when he served with the Worcestershire and Sherwood Foresters before becoming an MP, he knew "a lot" of ethnic minority servicemen in the Army who used perceived discrimination as an excuse for poor performance.

Announcing he had been sacked from his frontbench role, Mr Cameron said today: "The comments made by Patrick Mercer are completely unacceptable. I regret that they were made.

"We should not tolerate racism in the Army or in any walk of life.

"Patrick Mercer is no longer a shadow minister."

A Conservative Party spokesman confirmed that Mr Mercer had been asked to stand down, saying. "David Cameron asked him to step down, and Patrick Mercer did so."

Mr Mercer later issued a statement apologising for any offence his comments had caused.

The remarks, published by Times Online today, caused huge concern within his party, which has attempted to move into the political centreground under Mr Cameron. It also led to furious condemnation from race-relations campaigners and MPs.

He said: "I had the good fortune to command a battalion that was racially very mixed. Towards the end, I had five company sergeant majors who were all black. They were without exception UK-born, Nottingham-born men who were English - as English as you and me. They prospered inside my regiment, but if you'd said to them: 'Have you ever been called a nigger,' they would have said: 'Yes.' But equally, a chap with red hair, for example, would also get a hard time - a far harder time than a black man, in fact.

"But that's the way it is in the Army. If someone is slow on the assault course, you'd get people shouting: 'Come on you fat bastard, come on you ginger bastard, come on you black bastard.'"

Mr Mercer added that he knew soldiers from ethnic minority backgrounds who used racism as an excuse for poor performance.

"I came across a lot of ethnic minority soldiers who were idle and useless, but who used racism as cover for their misdemeanours," he said.

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