U.S. Big Oil giants Exxon Mobil and Chevron said May 2 they will steadfastly maintain their spending and stock buyback ranges in the face of tariff uncertainty and lower oil prices—despite reporting declining quarterly earnings year over year.

Exxon Mobil Corp. and Chevron Corp. are likely to shoulder more of the Permian Basin’s oil growth as independent producers cut back due to falling crude prices.

Chevron said net income fell by just over a third to $3.5bn in the first quarter, down from $5.5bn a year earlier, and slightly below analysts’ consensus estimates. Revenues fell to $47.6bn, down from $48.7bn a year earlier, as its global production remained flat.