The Road Haulage Association is calling on the government to raise the single carriageway limit from 40mph to 50mph.

It claims that motorists become easily frustrated and take risks when overtaking lorries.

In a letter to the Department for Transport, the association says roads would be safer if the limit was higher.

There are long stretches of the A66 where it is not safe to overtake, but motorists still try to get past, because they want to go faster than 40mph Jeff Marriott, Road Haulage Association

Jeff Marriott, Cumbria's area manager for the Road Haulage Association, thinks people are being endangered by the law as it stands.

He said: "Cars travel at 60mph, but anything over seven and a half tonnes is limited to 40mph.

"So we get this problem where the car drivers get frustrated at being stuck behind goods vehicles who by law can't go any faster.

"In Cumbria, the A66 is a good example. There are long stretches of that road where it is not safe to overtake, but motorists still try to get past, because they want to go faster than 40mph."

Raymond Lawson, the director of Lawson Haulage, in Cockermouth, agrees that the problem is widespread throughout the county.

'Queues horrendous'

He said: "It's a road safety aspect, and 40mph on modern day roads isn't enough. It should be increased to 50mph.

"The queues of traffic follow HGVs along the A-roads these days is horrendous. Cars takes chances, passing and coming back.

"Quite a few of my drivers have had speeding tickets recently, but it's purely because they're embarrassed at holding the traffic up."

But Mr Lawson denied that increasing the speed limit would actually endanger motorists.

He said: "Modern trucks are much safer, particularly when braking. Reducing the build-up of queues would definitely increase road safety."