A blueprint for the future of travel in Norfolk, which includes backing for the Norwich Western Link, is unlawful and should be withdrawn, say campaigners.

But Norfolk County Council bosses hit back, saying proper processes were followed and correct policies used to draw up the strategy.

The Local Transport Plan strategy is the council's vision, for up to 2036, to improve highways, encourage walking, cycling, bus and rail use and to deliver major projects like the Norwich Western Link and Long Stratton Bypass.

The strategy was adopted last year, but consultation is under way over its implementation plan - how the council plans to put it in place.

And critics, including members of the Green Party, have sent the council a letter, ahead of a potential legal challenge.

They claim the council acted unlawfully in starting public consultation when there are local elections and allege the authority is trying to rush the plan through.

They claim the council bypassed the authority's infrastructure and development committee.

The campaigners, also including the Wensum Valley Alliance and the Stop the Wensum Link group, criticised the council's approach of deferring publication of carbon reduction targets until a later stage of the development of the plan.

Denise Carlo, Green city councillor, said: "Monitoring shows carbon emissions for road transport in Norfolk have worsened since 2015 and yet the county is proposing more major road building which will further escalate emissions.

"It is little wonder the latest consultation avoids setting targets which align to recent government policies, as it would highlight the council’s poor record and its ability to meet government policy in the future.”

A county council spokesperson said: "We will be considering the letter and will respond in full in due course.

"We do not agree with any suggestion that the consultation is unlawful or that the proper democratic process has not been followed.

"The draft plan takes account not only of the government’s transport decarbonisation plan, but also the council’s own environmental policy that sets a target on our own estates for net zero by 2030."

Consultation at https://norfolk.citizenspace.com/consultation/local-transport-implementation-plan-4/ runs until May 2.