Kenneth Clarke, the three-times former Tory leadership contender, said Mr Mercer was a decent frontbench spokesman although he understood why Mr Cameron dismissed him. “Patrick has expressed his views rather foolishly, as he accepts. He was a good frontbench spokesman and is a good colleague, but he definitely does not hold racist views, though I do understand why David Cameron had no choice but to ask him to stand down."

Michael Ancram, a former Conservative shadow defence and foreign secretary and leadership contender, said: “I worked closely with Patrick as both shadow foreign secretary and as shadow defence secretary. I got to know him well and he is certainly not a racist.”

Former corporal Leroy Hutchinson, who served in Mr Mercer's regiment, backed their former colonel: “I am a black man, who served with Patrick for 12 years. I was promoted to corporal under his command. He never tolerated racism in the battalion and not a single one of his men would consider him to be racist."

Mr Mercer's constituents criticised the sacking. Sheelagh Hamilton, chairwoman of the Newark Conservative Association, said: “I am extremely angry that what has been said has been taken out of context and David Cameron has behaved precipitously. I think it’s all been done in a huge amount of haste. I am judging by the support he has received today from not just within this constituency, but throughout the country. I just think that without getting to the bottom of it, Patrick has been asked to step down."

Mike Quigley, the leader of Tory-run Bassetlaw District Council, said: “It seems to be that he has been a bit forthright about his own experiences in the Army. I would not have thought for one moment that Patrick Mercer would have intended a remark that’s racially offensive. Knowing the work he has done with the local Muslim community, it would be out of character.”

Richard Alexander, a cabinet member of the Tory-run Newark and Sherwood District Council, in Nottinghamshire, said: “We all say things in the heat of the moment that do not read too well in print, but I understand where he’s coming from. He’s an ex-Army man and is entitled to his robust views."

Remarks on the matter were flooding in on the Conservative-supporting website Conservativehome.com this afternoon, with opinion divided on the matter.

Backing Mr Cameron's decision, Alan Simpson wrote: "How can we try and convince the electorate that we are a changing party if we still have idiots such as this in the ranks?

A writer calling himself Malcolm added: "How many more times are our spokesmen going to say stupid things like this? Having said that, he could and should have been given the opportunity to apologise and retract rather than be instantly dismissed."

Peter Hatchet, another member of the public, wrote: "This is worthy of a sacking. In fact, it's a borderline 'Howard Flight' penalty. You can see somewhere there is some of point he's making but, Christ, he did he do this badly. Comments on issues such as these require extreme caution and very careful thought and consideration."

However, some writing on the site said that the Tory leader was wrong. Sam Ellis wrote: "Patrick Mercer is a fantastic Member of Parliament and the people of Newark and Retford are lucky to have him."

A writer called TomTom added: "Mercer is credible - at least he wore a uniform and did his duty....St Anne's is where Nottinghamsire police patrol with submachine guns to keep the drug gangs in order. Mercer is a real loss to the Conservative Front Bench."

Meanwhile, Roddy Piper questioned the credibility of the Tories' original response that Mr Mercer's quotes were a private matter. "I don't understand why Central Office originally said his comments were a personal matter and then a couple of hours later they suddenly decided the comments are not acceptable and sacked him?"

A number of other members of the public said Mr Mercer had been a victim of political correctness. "What Mercer said was wrong only insofar as politicians have to be politically correct in what they say and do, and as a professional politician he should engage brain before opening gob. But what he said is correct and it is a sad reflection that the truth now comes second to PC. That mocking laughter you can hear in the background comes from the ghosts of those who have always sought to ban free speech," a poster calling himself Essex boy said.

A writer calling himself Derek added: "It is no longer possible to tell it as it is, unless it is wrapped up in obscure language."

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