A campaign group has launched a long-threatened lawsuit against a district council’s handling of a major development blueprint.

No Adastral New Town (NANT) said it had been “left with no choice” but to mount a High Court claim that Suffolk Coastal District Council (SCDC) failed to comply with strict planning directives when it sanctioned the Core Strategy (CS) of its Local Development Framework.

In June, following a lengthy public inquiry, an independent inspector approved the controversial document, which sets out how a district will grow over the next 15 years.

NANT, along with Save Trimley Against Growth (STAG), disputed the validity of consultation into the proposals, while Waldringfield Parish Council claimed the whole process failed to meet EU environmental regulations - an accusation denied by the district council.

Now NANT is taking its protest to the High Court, claiming the council ignored Strategic Environmental Assessment Regulations and Habitats Directives (relating to wildlife and nature conservation) when outlining where 7,900 new homes will be built across the district - including the 2,000 at Adastral Park, Martlesham Heath, that sparked the group’s campaign, and between 1,000 and 1,400 in Felixstowe and the Trimley villages.

Janet Elliot, speaking for NANT, said: “We hoped that some detailed legal arguments would be dealt with during the planning inspector’s examination in public. Although the inspector sought clarity on some points, he appeared content with what SCDC told him.

“It is a view, and that of our legal team, that SCDC is still not complying. We really have no other course to take.

“It will ultimately come down to the judge’s decision but our barristers say we have a case - otherwise we wouldn’t be taking it forward.

“If, at any point, SCDC had been transparent, we may not have been led to this situation - but their minds have been made up.

“We will be asking the court to quash certain policies within the CS. We have evidence that points to SCDC’s allocation of 2,000 homes for Adastral Park at exactly the time BT submitted a planning application for the same amount. We don’t know their motivation, but we do know they have not been open to counter argument from that point.

“We have lodged our claim and now await due process. We are sure this could have all been avoided. Responsibility lies entirely with SCDC.”

In a writ addressed to SCDC, BT and the Secretary of State for Communities and Local Government, NANT claims the council failed to comply with the regulations and directives, and failed to properly engage in lawful consultation.

The CS was formally adopted on July 5 and renamed the Suffolk Coastal District Local Plan - Core Strategy and Development Management Policies.

Andy Smith, deputy leader and head of planning, said the council would “vigorously” fight any legal action. He added: “This strategy provides a cornerstone to allow us to properly plan and manage growth and development across our district, delivering much-needed additional homes, new jobs and improved infrastructure, while maintaining and enhancing the environment and quality of life which we all cherish. It also enables us to reject inappropriate or piecemeal development which does not meet the requirements of the strategy.

“In drawing up this strategy, we carefully balanced the need for growth, to ensure a strong local economy and access to housing for families in the district, against our commitment to protect the environment that makes this one of the most attractive places in the country to live, work or visit. Following extensive public consultation, our plan was examined in detail and found to be sound by an independent planning inspector.”