Such breaches included failing to maintain its independence over its audit of collapsed alcohol firm Conviviality.

The FRC said that the firm provided an unqualified audit opinion to Conviviality in 2014 in circumstances where the threats to independence were such that it should have resigned from the engagement.

The firm has received a severe reprimand from the FRC after it admitting that it had breached ethical standards between 2014 and 2017.

Grant Thorton has agreed to non-financial sanctions including a declaration that the audit of Conviviality did not comply with relevant requirements and a package of measures directed at improving the quality of future audits.

The measures include the establishment of an ethics board within the firm to oversee the firms future compliance with ethical standards. Grant Thornton had just two people in its UK ethics function in 2014. That number has since risen to a dozen and a further three employees are being recruited to the team.

Grant Thornton has also agreed to provide reports to the FRC for three years to prove its compliance. It will also be subjected to a review of its ethic function to identify any skills/resource gaps.

Grant Thornton staff will also receive increased training on relevant ethical issues.

Grant Thornton will also pay a sum of £207,000 in respect of executive counsel’s costs in the matter. The FRC initially fined Grant Thornton £3 million for the failures, but the fine was reduced to £1.95m for admissions and early disposal in relation to the Conviviality audit for the year to the end of April 2014.