The creation of a giant Brexit border control site off the M20 is likely to cost taxpayers a staggering £70 million, it has emerged.

Critics say the massive sums forked out on the government's Inland Border Facility (IBF) at Sevington, near Ashford, "could have been better spent elsewhere".

The controversial 230-acre site was built in order for checks on imports arriving in lorries from the European Union.

But earlier this year, KentOnline published drone pictures which revealed parts of the IBF - which has space for 1,700 lorries - were completely deserted.

In January, the Department for Environment Food and Rural Affairs (Defra) confirmed it has “no current operations” at Sevington “except a small presence” which “was temporarily available for holding pets during the Ukraine response”.

The total cost of the project had not been known until it was revealed at a meeting of Kent County Council's (KCC) governance and audit committee on Tuesday.

A report provided to the committee by external auditors Grant Thornton says: "We understand the most recent forecast of the total capital costs associated with the Sevington project is circa £70m."

Green county councillor Mark Hood said the lack of activity at the IBF showed the government had rushed into decisions.

"There was so much uncertainty that things were put in place at great haste and a lot of money could have been better spent elsewhere," he told the meeting.

"This was all completely avoidable."

While the Sevington IBF is funded by the government, KCC was tasked with procuring the contracts for building the site.

The auditors also flag up concerns that the council had not been checking contractors had completed the work they were paid to do.

In a section of the report devoted to the Sevington site, Grant Thornton say they had identified several large transactions and had requested details on some of these payments.

They also asked for evidence that work had been completed and that an independent chartered surveyor had been brought in to do that.

However, the auditors say that the council was unable to provide such evidence and contractors were paid regardless.

Grant Thornton say they had found no "material mistatements" in the council's finances but were critical.

“This is a control weakness because without that evidence, management cannot be assured the supplier has completed the work to the required specification," the auditors write.

“We have concerns that the governance and controls KCC has put in place are not effective to mitigate the risk."

The report recommends that the council obtains the necessary assurances from government departments about the completion of work before making any payments.

“As it stands the council is party to potential inappropriate payments,” it concludes.

Speaking after the meeting, Cllr Paul Bartlett, deputy leader of Ashford council and a county councillor, told KentOnline the figure of £70m was "an awful lot of money."

As to the auditors' findings, the Conservative said it was "poor" the council had not properly monitored the work, saying that it was public money being spent and a legitimate concern.

In a statement, KCC said the recommendations made in the report would be considered at the next governance and audit committee.

The Sevington site which was opened in January 2021 has been controversial from the outset and activity levels have diminished, with reports of days when only a few lorries are tested or checked.

Residents living near the site have complained about light pollution, claiming it's as bright as Wembley Stadium.

There have been reports that it could become a lorry park in the event of disruption on the M20 - although its capacity is relatively low at 1,700.

HMRC has been contacted for comment.