The 1980 and 1984 Olympic 1,500 metres champion insisted the London Games would have the toughest possible testing measures to catch out dope cheats.

The issue is "absolutely essential" to the success or failure of the world's biggest sporting event, Coe said at the party conference of Britain's main opposition Conservatives in Blackpool.

"We have to be a zero tolerance Games," he said.

 

"It's everything I've stood for for the last 30 years.

 

"I was the first person to speak at an International Olympics Committee (IOC) congress as an athlete about the problems of drugs in sport.

"We take it very, very seriously. It is absolutely at the centre of everything we believe.

"Sport is about free, open and fair competition.

 

"We want these Games to be for everyone and they cannot be for everyone, particularly as competitors, if you have a small group that decide to cheat."

Coe warned the testing procedures were likely to be the toughest ever faced by athletes.

"Every Games is tough, but of course we want to make sure that we are absolutely abreast with every detective mechanism that we've got available to us," he said.

"We've got all the testing procedures that the IOC will bring, all our international federations and of course we're now building our medical team at the local organising committee.

"That will be the full panoply of everything that is at an Olympic Games, with the advantage of being able to use even greater and more modern technology over the next five years."

Coe will also have the benefit of hindsight after next year's Olympics in Beijing.

He is confident the measures in place for the 2008 Games are up to scratch for catching out those attempting to cheat on the world's biggest stage.

"In every assessment, Beijing is turning out to be a spectacular Games," he said.

"The IOC of course is responsible for the testing at a Games and the IOC takes every Games very, very seriously, winter and summer."

Jonathan Edwards, Britain's triple jump world record holder, said he expected dope cheat athletes would be caught out in Beijing due to the rigorous testing system now in place.

"I think it will crop up because we take it seriously," he said.

 

"Due to the amount of out-of-competition testing that goes on, and in-competition testing as well through the Games - I imagine the top three will be tested, probably one other randomly out of the top eight - it is very, very difficult to cheat.

"There will be those who will by definition be one step ahead of the system but I think they will be by far the minority, simply because the level of subterfuge and financial clout needed makes it possible for only very few athletes."

The former Olympic, world and European triple jump champion claimedhe never came across drugs in athletics and reckoned it was far from widespread.

However, he added that athletes were often exposed to being doped by their coaches due to their reliance on them off the track.

"I do think athletes are very vulnerable," said the retired 41-year-old, now the athletes' representative on the London 2012 organising board.

"They're desperate to achieve their dreams.

 

"We trust other people to do all the other little bits and pieces for us, so we can focus solely on getting ourselves in the best shape.

"I can envisage a scenario whereby an athlete is given a supplement by their coach, the coach says, 'take that, it's OK, don't worry.'

"The athlete trusts that person's judgement and the advice they are giving to them, the athlete takes the supplement -- and it's actually illegal.

"That is not impossible.

"In the end, the athlete does have to take responsibility, but you do need to look beyond that to the coaches and potentially systems that try to cheat."