Eurasian Natural Resources Corporation (ENRC) has commenced legal action against the Serious Fraud Office (SFO) in the latest twist in a long-running dispute.

ENRC has applied to the High Court for a judicial review, claiming that the SFO’s decision to park an independent inquiry into how the SFO handled an investigation into the mining giant was ‘unlawful, unreasonable, disproportionate and unfair’.

ENRC is the subject of an ongoing, six-year SFO investigation into alleged fraud, bribery and corruption. ENRC denies all allegations against it.

Sir David Calvert-Smith, former director of public prosecutions, was appointed to conduct the SFO’s independent review in November 2018. However, the probe was dropped after ENRC filed a £70m High Court claim accusing the SFO of misfeasance in public office earlier this year.

The SFO told the Gazette that it halted the inquiry ‘until the conclusion of civil proceedings because they cover the same ground. At the close of civil proceedings the SFO will consider whether there is good reason to allow the review to continue’.

In its Statement of Facts and Grounds for Judicial Review document, ENRC said: ‘The Calvert-Smith Review was intended and designed to perform functions distinct from the misfeasance proceedings.’

The SFO said it ‘does not accept ENRC’s position in its judicial review claim and our investigation into ENRC and others is ongoing’.

Last month, the mining company filed a High Court claim against a former prime minister of Kazakhstan, alleging he leaked confidential information to the SFO.