The county council temporarily lost £9.1 million after a member of staff typed in the wrong bank account number.

The millions were due to be transferred back into a county council account on August 7 this year, after a short-term investment into a money market fund.

But on August 8 - the day after the money was due - council officers found it had not arrived.

An internal investigation discovered that the wrong bank account number had been included on the instruction letters from the county council, with two of the digits wrongly transcribed.

As a result the money had not been paid back, but had instead been returned to where it had been sent from.

The money was only returned to the council on August 9 - two days after the payment was due.

The treasury control failure was reported at a meeting of the council's audit committee on Friday, December 6, which heard that the council's account number had been mis-typed by a member of staff on the request form.

A report to the committee pointed out that those details should have been reviewed by a further member of staff before being signed off, but the review failed to pick up the error and may not have occurred at all.

As a result, the council lost interest on money totalling around £300.

The county council has since reviewed all of the instructions that had been sent in July and August and, due to the "serious nature of the failure", an internal review of controls and procedures was conducted in October.

Chairman of the audit committee, Conservative county councillor Frances Button, stressed that this was one payment out of the many thousands processed by the finance team in a single month.

Cllr Button said while any error was "regrettable", and 100 per cent performance was expected all the time, this was one error out of many thousands of payments.

She also said she was proud of the council's finance officers for picking it up and for rectifying it immediately, as well as for the additional work to enhance finance controls.

The committee also heard that the county council is also projecting an underspend of £296,000 for its capital financing and interest on balances payments.