Don't make the mistake of thinking that the current battle for the leadership of Britain's Conservative party is only about politics. As well as the merits of the two candidates, David Cameron and David Davis, the red tie's status as the male wardrobe's most trusted way to convey authority is also under scrutiny.

Ronald Reagan is credited with importing the device from Wall Street to politics. To accentuate the positive effect the colour brings to the face on television, "the great communicator" had his collars cut away and opted for the most substantial Windsor knot.

From then through until 1997, when Tony Blair and Gordon Brown brought their own red tie affections to the offices of prime minister and chancellor of the exchequer, respectively, and even today, as George W. Bush reaches for red when live, the carnelian neckerchief has reigned unchallenged as the geo-political power accessory of choice.

But if Cameron, who recently told the Centre for Policy Studies that wearing a suit is good for your self confidence, is declared the new leader of the Conservatives on December 6, the red tie will begin to be marginalised. Throughout the campaign Cameron has depended largely on lilacs and pink. Even during a national televised debate with Davis, he opted for blue, although he could not resist red this week when addressing the CBI, the employers' group.

The red tie's public demise cannot come soon enough, according to Judy Fearn, an image consultant of two decades who has worked with some of Britain's most senior politicians of recent years. "We have moved on," she maintains. "People now realise that red is just too much, like big hair."

Richard Anderson, the Savile Row tailor, agrees there has been a move away from strong red. "These days, men like shirt, suit and tie to float together."

Fearn acknowledges the past effectiveness of red, especially on television. "We are bombarded with visual images which register ahead of any audio message and red immediately says 'I am in charge'. Reagan, coming from a movie background, understood this. But, style-wise, the look is now dead. Like yellow, it seems dated."

Politics is mirroring business, according to Fearn. "Dress down culture means the IT consultant and hip city guy might not even wear a tie," she suggests. If a tie is mandatory, Fearn recommends blue or burgundy. "Public figures are more caring now, or at least like to appear more caring. Burgundy says 'trust me' while blue is universally safe."

Anderson dates the beginning of London's drift away from "Liverpool" red to "the last couple of years". But he also reports there is little sign of a shift in Washington. "A diplomat was in recently for a fitting and he was bemoaning the very fact," says Anderson. The doyen American columnist, Frank Deford, who declared "the day you see a politician wearing purple is the day we have a truthful person in politics" may be kept waiting yet.

While Gordon Brown, Blair's heir apparent, waits, himself, for Britain's top job he remains committed to red. Timothy Everest, the bespoke tailor who has made suits for Brown, does note with all his clients a general trend in ties away from the "Ferrari" shade. "In business, red is a sign of formality. Also some in today's financial world already acknowledged as successful aren't now compelled to make strong statements with neckties."

Everest does warn that on television blue can appear almost black. He believes that red will still remain a popular contrast with dark suits and for those whom the colour gives added gravitas. "Maybe also when there are plans for a boardroom coup," Everest jokes.

Interestingly, David Cameron, whose office maintains his choice of tie is based on "style rather than any politics" has also been recently fitted for a suit by Everest. In the future, ties may be the only big difference in style between the leaders of Britain's political parties.

Richard Anderson warns of a more serious danger. "Width and colour of tie is often an indication of how affluent are the times," he explains. If the narrow blue is indeed on the way back, we may be about to experience a recession.

Colin Cameron's latest book, Dawn Till Dusk, is published by Highdown

www.timothyeverest.co.uk; www.richardandersonltd.com