Oil and gas will play a critical role for a long time to come, Exxon Mobil CEO Darren Woods said Friday, adding that the question was whether they will continue to be used as fuel.

While future technological breakthroughs might see a change in the burning of hydrocarbons, they will continue to be used for other purposes, such as in the medical sector, Woods said.

"Crude oil and hydrocarbons are going to play a critical role in everybody's life for a long time to come," said Woods.

Carbon emissions from fossil fuels such as oil and gas, but also coal, are a major contributor to climate change

"The question is, do you continue to combust them? And that, I think, will change with time, depending on how technology develops," he told Reuters on the sidelines of the Sustainable Innovation Forum in Sao Paulo, Brazil.

The South American country is hosting United Nations COP30 climate conference which this month in the city of Belem.

Earlier this week, the UN said the world would overshoot its goal of keeping global warming below the 1.5 degrees Celsius target set at the Paris climate conference in 2015.

Woods said that policymakers are taking decisions without the full picture, adding that effective carbon accounting was needed to properly track emissions.

"Without a mechanism to accurately account for the carbon that's being emitted across economies, net zero is just a slogan," Woods said.

"You have to actually understand where the emissions are coming from and have a ledger-based system that gives credibility to those emissions as they occur along a value chain," he added.