The M25 between Surrey and Watford was named as a hotspot

The southern part of the M1 topped the list for jams, followed by the M25 between junctions nine and 20.

Congestion was measured in the 12 months up to April 2007 for the report by Trafficmaster.

RAC Foundation executive director Edmund King urged drivers to "get smarter" by using traffic information and in-car technology to avoid jams.

TOP FIVE CONGESTION HOTSPOTS M1 Home counties J6A-J11 M25 Western sector J9-J20 M25 Northern sector J21-J28 M6 West Midlands J3A-J11A M6 North Midlands/North West J11-J21A

"Travelling out of the peak or working from home one day a week can have great benefits for the economy and environment," he added.

Trafficmaster spokesman Philip Hale said: "We all know where our local congestion blackspots are.

"The problem is we all continue to use these roads when they're most congested, despite knowing we're likely to hit a traffic jam."

The report also highlighted how using alternative routes can save time.

Mr Hale said the first step in tackling the problem was to identify it and avoid it.

"You can use alternative routes to literally save hours," he said.