An influential Labour MP has demanded Big Four accountancy firm PwC answers questions over its role in auditing BHS before it was infamously sold for £1 in 2015.

Frank Field, who chairs the Work and Pensions Committee and presided over the parliamentary inquiry into the collapse of BHS, has written both to PwC and a former senior partner at the firm to ask for more details about the quick sale of the retailer.

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The demands come only a week after an unprecedented £6.5m fine was levied against PWC by the UK accountancy watchdog.

The Financial Reporting Council (FRC) hit the Big Four company with the fine over misconduct in relation to its auditing of BHS two years before it collapsed in 2016.

The audit of BHS was signed off five days prior to a £1 sale – two months earlier than in previous years, in which billionaire retail tycoon Philip Green sold the firm to Retail Acquisitions.

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Field has asked former senior partner Steve Denison, who was banned from audit work and slapped with a £500,000 penalty over his own involvement in the auditing of BHS, whether he was present at the meeting in which BHS was sold to Retail Acquisitions for £1.

The Labour politician has also asked a wider series of questions to PwC over its auditing of both BHS and Taveta Group around how many members of PwC staff were involved in the audit and whether there were safeguards in place to prevent potential conflicts of interest.