The watchdog will examine the 2011 and 2012 audits of ENRC, which begun without pre-announcement, according to a report from the Times.
Between 2006 and 2012, PwC received more than £50m in fees for work in relation to advice it gave the mining company on its 2007 London Stock Exchange flotation, its audit work and other services.
Five years ago, the Serious Fraud Office (SFO) opened a criminal enquiry into the Eurasian National Resource Corporation (ENRC) – acquired by Eurasian Resources Group (ERG) in 2013.
The enquiry, which is ongoing, is into allegations of fraud, bribery and corruption in ENRC’s acquisitions of assets in Kazakhstan and Africa.
In October, the SFO charged ERG CEO Benedict Sobotka with failing to appear for an interview without a reasonable excuse.
In the same month the SFO suffered a defeat in a Court of Appeal ruling over the disclosure of ENRC documents that it thought would prove alleged financial wrongdoing.
This is the first regulatory investigation by the FRC into PwC this year, however, the watchdog currently has two other open investigations into the firm – for Redcentric and BT Group, announced in February and June last year respectively.
In June, the firm was fined a record £6.5m after it, and audit partner Steve Denison, admitted misconduct to the FRC on the accounts of BHS.
In January, the FRC announced an investigation into KPMG’s 2014 to 2017 audit of now collapsed construction company Carillion and in July announced another investigation into the Big Four firm’s work on now defunct drinks retailer Conviviality.
A month earlier in June, the watchdog opened an investigation into the 2015 and 2016 audits of construction supplier SIG.
It is not only the Big Four’s audit work that has been scrutinised, in November the FRC opened an investigation into Grant Thornton’s audit of café chain Patisserie Valerie after potentially fraudulent accounting irregularities were uncovered.
PwC, FRC and ERG are not commenting at this stage.