Two district councils and Suffolk Chamber of Commerce have backed proposals for a new link road to be created at Copdock Interchange.

Babergh and Mid Suffolk councils have backed the new link rather than simply an increase in the capacity of the existing roundabout - the other proposal from National Highways.

But the councils' backing for the new road is not supported by opposition Green Party groups on the two authorities - they have warned that any changes will merely increase the amount of traffic.

The councils say the new link road would be the best way of ensuring an easy flow of traffic between the ports of Felixstowe and Harwich and other parts of the country - and it would also cause the least disruption to local communities.

Without major improvements they fear local "rat-runs" would become busier - already the old A12 through Copdock and Washbrook is quite busy during rush-hours. And National Highways are being urged to ensure any proposals adequately address noise, light and air quality impacts on local residents.

Clive Arthey, Babergh District Council’s cabinet member for planning, said: "Unimpeded traffic movement between Felixstowe and the London/South East region is essential for the prosperity of Suffolk and would allow us to take a further step towards an integrated sea, road and rail infrastructure network.

“In the meantime, any improvement to the junction that stops traffic taking alternative routes via Old London Road, and the villages south of the A14, will improve the quality of life of our residents in those areas.”

Andy Walker, from the chamber, said: “Suffolk Chamber of Commerce prefers Option 4 (link road) in principle, as we believe this option will optimise economic growth in Ipswich and South Suffolk.

"Furthermore, a new link road will provide longer term resilience, safety improvements and help remove some of the congestion around the existing junction.

"A new link road would also alleviate the queues on the A14 westbound carriageway turning left to the A12. In addition, Option 4 would help improve safety, add elements of active travel such as cycling and walking and provide the most tangible benefits for our logistics and port sectors.”

Cllr David Burn, Mid Suffolk District Council’s cabinet member for Planning, said: “We have worked closely with National Highways in preparing our Joint Local Plan and we recognise the Copdock Interchange as critical infrastructure for our districts. There is a clear need to focus on improvements to the A12 and A14 and the junction is also a key issue identified in Suffolk County Council’s Local Transport Plan.

“However, any development proposals will also need to adequately address the environmental impact on local residents, and we welcome further discussions to explore opportunities to secure benefits for our communities.”

However Babergh Green councillor Leigh Jamieson issued a statement from his group saying: "This is not a junction improvement scheme, it is a traffic increase scheme, at considerable cost to the tax payer nationally and locally.

"We should be investing in more capacity for rail freight from Felixstowe and better bus, cycle and walking links, not incentivising more road traffic.”