Erginbilgic, who joined BP in 1997, oversaw the expansion of the downstream business, which includes refining, retail and petrochemicals, into electric vehicle charging and added thousands of petrol stations in developing economies such as India and Mexico.

The announcement on his departure comes two days after Looney took the helm from Bob Dudley.

It follows Chief Financial Officer Brian Gilvary's decision to leave the company in June. Looney's successor as head of upstream has yet to be announced.

Erginbilgic's successor will be announced separately, BP said.

"Under Tufan's leadership, BP's Downstream has been at the heart of our return to growth; what he has achieved in this time is extraordinary," Looney said in a statement.

Downstream helped boost BP's profit after the 2014 oil price collapse, offsetting weaker revenue from the larger oil and gas production division.

The expansion in retail and petrochemicals are seen as key for BP as the world shifts away from fossil fuels, focusing on low-carbon fuels and plastics whose demand BP expects to continue growing sharply in the coming decades.

(Reporting by Ron Bousso; editing by Jason Neely and David Evans)

By Ron Bousso

Stocks treated in this article : London Brent Oil, WTI, BP plc