Oilfield company Petrofac has hired Ashurst litigation partner and City of London Law Society (CLLS) chair Edward Sparrow, as it faces an ongoing Serious Fraud Office (SFO) investigation into its connection to the Unaoil corruption scandal.

Petrofac confirmed in a statement on Wednesday (9 August) that as a senior external specialist, Sparrow will oversee the company's "management of, and response to, the investigation".

The FTSE 250 group was first linked to the Unaoil corruption scandal last year, after leaked documents indicated Monaco-based Unaoil paid bribes on behalf of oil companies including Petrofac to win contracts.

The SFO announced in May this year that it was looking into the activities of Petrofac, its subsidiaries and their officers, employees and agents for "suspected bribery, corruption and money laundering".

Mishcon de Reya business crime partner Jo Rickards is advising Unaoil on the overall case. The company had previously instructed Clifford Chance on the matter.

The allegations against Unaoil first came to light in March last year following an investigation by Huffington Post and Australian broadsheet The Age, based on a cache of leaked documents. The paper reported that between 2002 and 2012, Unaoil bribed officials to help its clients win contracts across the globe.

According to the reports, Unaoil paid bribes to local companies and state agencies to secure contracts for clients including Rolls-Royce, US giant Halliburton, Australia's Leighton Holdings and Korean companies Samsung and Hyundai.

The news outlets claimed Unaoil's activities spanned a wide selection of countries including Iraq, Kazakhstan, Iran and the United Arab Emirates.

Ashurst declined to comment. Mishcon de Reya declined to comment.