Britain's two worst speeders were clocked doing 146mph on the M25 in Kent, a safety charity has revealed.

The Institute of Advanced Motorists (IAM) has revealed the drivers were caught clockwise at Swanley and anti-clockwise at Clacket Lane Services last year.

Figures from a freedom of information request show three other cases in Kent where speeds were recorded in excess of 140mph.

The charity says the worrying statistics show an improvement in driving skills and attitude is needed to reduce the number of deaths on British roads.

Sarah Sillars, IAM chief executive officer, said: “It is disheartening to say the least that some road users are showing such disregard for the safety of all other road users – pedestrians, cyclists, motorcyclists and other drivers.

"These individuals are playing with their own lives and others – they are all accidents waiting to happen" - Sarah Sillars, IAM

"At speeds of 140mph an individual is travelling at nearly two-and-a-half miles a minute. At that speed it is simply impossible to react to anything that might happen in front of you.

"It is also impossible to handle corners, gradients, street furniture and junctions with any effectiveness.

"In short, all these individuals are playing with their own lives and others – they are all accidents waiting to happen and it requires a major shift in the attitudes of these people to think about safety.”

Other speeding offences highlighted include 145mph on the M6 toll road, 141mph on the A1 Great Ponton Northbound road and 140mph on the A5 Crick Eastern Verge road.

In East Grinstead, one driver broke the limit by almost 100mph after doing 128mph on a 30mph road.

Last year, the highest speed caught on camera was also in Swanley, where one motorist was recorded doing 149mph.

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