(Bloomberg) -- A former oil executive pleaded guilty to five counts of corruption in the U.K. as part of one of the white-collar financial crime prosecutor’s biggest bribery investigations.

Basil Al Jarah, who was oil services company Unaoil Group’s partner in Iraq, pleaded guilty to conspiring to make corrupt payments in connection with contracts to supply and install moorings and oil pipelines in southern Iraq, the Serious Fraud Office said in a statement. Al Jarah entered the plea on July 15, but the court only permitted it to be reported on Friday.

Three other former executives have been charged in connection with the case, which the SFO started investigating in March 2016. They are due to go on trial in January.

To contact the reporter on this story: Franz Wild in London at fwild@bloomberg.net

To contact the editor responsible for this story: Anthony Aarons at aaarons@bloomberg.net

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