Costs of a link road between Tendring and Colchester which have spiralled by more than £20million could rise by even more to allow stalled crucial land purchases to proceed.

But Essex County Council has not only asked the government for an additional £21m to be released to pay for the increased costs of the new A133/A120 link road east of Colchester but for the deadline for completion to be extended to August 2025.

The contract with the government had stipulated the road had to be completed by 2024.

The government had allocated £99m of Housing Infrastructure Fund money for the delivery of the link road and a rapid transport system to enable to development of a 9,000-home garden town on the Tendring and Colchester border.

The county council – which gave planning permission for the road at the time costed at £70m in November 2021 – has admitted there is a risk that Homes England and the Treasury will not be willing to fund the cost escalation of £21.25m in full or are not willing to the full programme extension.

Should land be acquired late there is a risk that this will delay the overall construction programme and may result in additional mitigation works, this could lead to increased costs “that are not currently quantifiable”.

Any delay may also place further pressure on the Homes England funding deadline, the county council has said.

Planning campaigner Rosie Pearson said: “Essex County Council was warned that the contract for funding for the link road was impossible to keep, because it sets an impossible 2024 deadline. If the deadline is missed, the council cannot draw down any more money from Homes England.

“In addition the council was warned that the contingency built into the project to cover the risk of costs spiralling was only half what it should be. Yet, sure as eggs as eggs, as with most public projects, costs have spiralled.”

The county council has said that before it can begin construction of the road it needs to secure ownership of the relevant land.

A spokesperson for Essex County Council said: “On a large scale infrastructure project with several different landowners, it is normal for land owner negotiations to take some time as the scheme progresses through the design stages.

“Whilst it remains the ambition to acquire land by agreement, ECC is preparing Compulsory Purchase Orders to ensure the overall programme can be met.

“The council would not comment on any individual negotiations.”