Councillors are preparing to lobby for improved transport links to the south coast as Dorset’s “inadequate” roads are blamed for suppressing the economy.

Councils and businesses across the region have set out the case for better transport links between the Channel ports of Poole and Southampton and the M4 corridor.

Bath and North East Somerset, Wiltshire, Dorset and Poole councils, together with local enterprise partnerships, on Friday (20) published the South of England North-South Connectivity Prospectus.

The prospectus, which lays out the economic case for improved north-south links, will be used to urge the government to include the plans in the next Road Investment Strategy.

Councillor Daryl Turner, Dorset County Council’s cabinet member for natural and built environment, said: “Dorset’s economy has been artificially suppressed due to wholly inadequate transport links to our ports and markets, particularly from the north.

“Improved links offer a huge potential for growth throughout the region.

“The government already acknowledges that an improved connection between the M4 and the South Coast is desperately needed; the time has come for them to commit to making it happen.”

The report estimates that if the government adopted the scheme it could create 30,000 new job for Dorset and generate a potential £20.5 billion into the region’s economy.

Jim Stewart, chief executive of Poole Harbour Commissioners, said: “The absence of an effective north-south link has hindered growth in Dorset’s economy for decades.

“Dorset’s economy requires urgent investment in a viable north-south road solution if it is to achieve its full potential.”

A particular problem, is the large number of heavy good vehicles travelling between the ports and the motorway network.

Councillor Bridget Wayman, cabinet member for highways at Wiltshire Council, said: “The increasing level of congestion is holding back the economic growth of the area including plans to create new jobs for the local communities.

“We have now created a compelling case for investment and seek the support of the government to deliver these much needed improvements.”

The prospectus has been published just days after key players in Weymouth and Portland renewed support for a western relief road through the town.

Tim Bowles, West of England Mayor, said: “To address transport and congestion issues in the West of England region, we need to work closely with our neighbouring authorities as roads don’t end at council boundaries, and many of us live work and travel across the region.”

To formally advance the case for improved north south links, the Secretary of State for transport must request a strategic study be carried out by Highways England.

If the Government considers this proposal to have sufficient potential to go forward it will form part of the next Road Investment Strategy.