Oilfield services provider Petrofac lost out on $10 billion worth of contracts globally due to a probe by Britain’s Serious Fraud Office into dealings in the Gulf, its finance chief said.

Petrofac shares, which have lost nearly half of their value since the SFO first announced its probe in 2017 as part of a wider investigation into Monaco-based oil and gas consultancy Unaoil, fell as much as 6.4 per cent.

In February, the SFO said Petrofac’s former head of sales, David Lufkin, had pleaded guilty to 11 counts of bribery related to oil deals in Iraq and Saudi Arabia.

The SFO said it was continuing its investigation into Petrofac’s use of agents in jurisdictions including the two countries.

"The timing of those bids coincided with the SFO’s announcement... that inevitably ... raised concerns amongst all stakeholders," Chief Financial Officer Alastair Cochran said on a call with analysts on its trading update.