The reserve update, which is required annually by US regulators, comes as the largest publicly traded US oil producer has been spending heavily under Chief Executive Darren Woods on new fields and projects to reverse weak oil and gas production.

Exxon said it added 4.5 billion oil-equivalent barrels of proved oil and gas reserves in 2018, bringing its total to 24.3 billion oil-equivalent barrels at the end of 2018. Proved reserves are those considered economically and geologically feasible to produce in the near future.

The 2018 additions put the company's reserves life at 17 years based on current production rates.

"Multiple new discoveries offshore Guyana, continued growth in the Permian Basin and a strategic acquisition in Brazil greatly enhanced our already strong portfolio of high-quality, low-cost-of-supply opportunities," Woods said in a statement.

Exxon plans to increase capital spending to $30 billion this year from $26 billion in 2018 as it expands operations in the Permian Basin of West Texas and New Mexico and develops large- scale projects in Guyana and Mozambique.

The US oil major cited significant additions from shale and other unconventional sources, which added 1.2 billion oil-equivalent barrels. Higher oil prices last year contributed to proved reserves additions of about 3.6 billion boe.

Overall reserves were reduced by 800 million boe because of future production reductions at a Netherlands gas field, the company said.

Exxon's stock gained 14 cents on Tuesday to $78.64 as oil futures inched higher and the overall stock market dipped. The company's shares are up about 1 percent in the past 52 weeks.