The UK Financial Reporting Council (FRC) will prohibit external auditors of financial statements for periods ending on or after 15 June 2014 from using internal audit staff as "direct assistance" members of the audit team.
The ban is aimed at safeguarding against conflicts of interest as the FRC attempts to ensure external audit independence.
FRC board member and chairman of the Audit and Assurance Council Nick Land said: "Prohibiting direct assistance supports stakeholders’ expectation that external auditors should be free from threats to their independence."
The FRC first announced its intention to prohibit the use of internal audit staff in February 2013, however a consultation revealed a logistical issue for audits that had already begun when the prohibition came into effect.
To combat this, the prohibition is being applied prospectively.
Land concluded: "In determining the effective date of the prohibition, the FRC has taken into consideration that planning the use of the work of internal auditors may take place early in the financial period being reported on."
Other revisions to the FRC’s auditing and ethical standards to reflect the revised international auditing standards on the external auditor’s use of work carried out by internal audit will have the same effective date.