BP on Tuesday reported a deeper-than-expected 48% drop in net profit to $1.4 billion on weaker gas trading and refining results and announced the departure of its strategy chief as it tries to shore up investor confidence.

BP said it would return less cash to shareholders as market uncertainty and weaker oil prices weighed on its outlook while the British energy major’s profit came in worse than expected. The London-based oil-and-gas giant said Tuesday that underlying replacement-cost profit–a metric similar to net income its U.

U.S.-listed shares of BP (BP) fell in premarket trading Tuesday after the British energy giant posted lower-than-estimated first-quarter earnings and reduced its stock buyback as increased economic uncertainty weighs on oil prices.