Theme park bosses hoping to build a £2.5bn attraction in Kent say a decision to protect wildlife and habitats on the proposed site is "unreasonable and unjustified".

The team bidding to build the London Resort on the Swanscombe Peninsula between Dartford and Gravesend have now formally rejected the status granted by Natural England earlier this year.

A consultation calling for views on the awarding of SSSI (Site of Special Scientific Interest) status by the government's nature advisory group closed this week.

The final decision is set to be made by the Department for Communities and Local Government and campaigners fighting to protect the site say confirmation of the status needs to be made quickly in order to grant the marshes full legal protection.

The SSSI status does not prevent development on the site but means any plans have to seriously take into consideration ways to protect the environment and the affected area to protect the landscape and wildlife within its boundaries.

London Resort Company Holdings (LRCH) has now called into question the validity of Natural England's decision saying it is in conflict with its own guidance on how SSSIs are selected and ecological practices.

The 13-page document submitted to Natural England criticises the agency on “grounds of the robustness of the evidence base, the lack of reasoned judgements by Natural England as required by the guidelines and Natural England’s failure to take a reasonable and proportionate approach”.

LRCH claims the body has ignored the latest ecological survey data carried out in 2020. The company added it has been carrying out its own environmental survey regularly for almost a decade.

It also questioned "greater weight" had been placed on analysis in 2012 and 2015 compared to more recent studies – something it says contravenes Natural England's own guidance to use data no more than three years old.

The company says it feels the "absence of justification and evidence" has been designed to "frustrate the development consent order" submitted to the Planning Inspectorate seeking planning permission to build the theme park dubbed the UK's answer to Disneyland.

LRCH says it plans to invest £150m to enhance habitats and mitigate the environmental impact of the park plans, which it adds aims to be "one of the most sustainable, global leisure and entertainment destinations in the world".

This includes creating more than eight miles of new pathways and other ecological improvements.

In its objection LRCH notes the land has been unmanaged for several decades and if that trend was to continue would see a "decline in its ecological value and reduction in biodiversity".

Andy Martin, director of strategy and communications for London Resort, said: “Sustainability has always been at the core of our vision. Our proposals show how we can deliver millions for the economy and thousands of jobs for the region while protecting and enhancing natural habitats.

“Natural England’s approach to designating the whole of the peninsula as an SSSI is at odds with that vision and, with the continuing degradation of much of the site, is sadly at odds with protecting nature.

Mr Martin added: “The selection and notification of the site as a SSSI was not made in reliance upon compelling or robust scientific evidence, but by the submission of the DCO application.”

“The evidence obtained from the 2020 analysis substantially weakens the case for the notification of much of the site as a SSSI and is one of the key reasons behind our objection.”

Buglife, RSPB, Kent Wildlife Trust and CPRE Kent joined forces to campaign for the greater protection for the site.

Speaking earlier this week, Craig Macadam, director of conservation at Buglife said: “Recent surveys have revealed that the Swanscombe Peninsula is one of the most important sites in England for rare invertebrates.

"However the site could be lost if plans to build the new London Resort theme park are approved, so we really need the notification swiftly confirmed and the site afforded full legal protection.”

The RSPB has repeated its calls for the theme park plans to be withdrawn and said it was "inappropriate" to be regarded as a nationally significant infrastructure project – something normally reserved for major roads, airports or power stations.

Nick Bruce-White, RSPB operations director for southern England, said: "This theme park must not take precedence over the species and habitats that it threatens; the developers must withdraw their application.

“If the SSSI is confirmed, and the development is still consented, it will be one of the largest ever single losses of nationally protected habitat in UK. We cannot allow this to happen.”

London Resort was granted a four-month extension following the SSSI decision in March to allow it to amend its plans in accordance with the new protected status.

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