Genel, the Kurdistan-focused oil firm founded by former BP boss Tony Hayward, has been rocked by a second executive quitting in a matter of weeks.
The firm's chief financial officer Ben Monaghan will depart in less than a month's time, it announced this afternoon.
The exit comes as Hayward himself also leaves the London-headquartered group this month.
Shares in Genel tumbled in the minutes after the 1pm revelation. While they have parred back some of the losses they are currently trading over seven per cent down on yesterday's closing price.
Genel gave no reason for Monaghan's swift departure. Murat Ozgul, the firm's chief executive said: "Ben has been a very valuable member of the Genel team. On behalf of everyone here, I would like to wish him all the best in his future career."
Hayward, who was replaced as BP boss in 2010 following the Deepwater Horizon oil spill, formed Genel in 2011. Nat Rothschild partnered the 60-year-old in a $2.1bn deal to buy the Turkish-based firm with interests in the Kurdish region of Iraq. He signalled his intention to leave his post as chairman of the firm in April.
Genel has struggled with writedowns and lower production in recent years. The firm, once valued as much as £3.1bn, is currently trading with a market cap of £280m.