Community leaders and transport experts have welcomed the scheme.
Robin Cummins, of the RAC, said: "We would welcome anything that is going to put another lane on the motorway and get the traffic moving.

"Not only is it going to help reduce congestion, it will improve road safety as well."

Brian Gregory, chairman of the Association of British Drivers, said: "In these sorts of areas the more lanes you have the better.

"If you could keep three lanes on the M6 and two lanes going off to the M55 that has got to be good news."

Preston Council leader Ken Hudson, who has called for an extra motorway junction near Garstang, said: "I think this would be an absolutely ideal solution to the problem and at the same time they should look at an extra junction."

But not everyone agrees it is the answer.

Aiden Turner-Bishop, of the Lancashire-based Campaign for Better Transport, said: "It is not really going to solve the problem of increasing traffic.

"It might be a temporary fix but it is not a long-term solution."

Coun Stuart Greenhalgh, who covers the Garrison ward of Preston, was "intrigued" to hear of the proposed motorway expansion and said: "I can't really see it having an effect on my ward, but by doing that it might increase the likelihood of making 31A a full- blown junction. I would have concern about that."

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