The International Energy Agency (IEA) has warned that production from mature oil and gas fields worldwide is declining faster than expected, raising fresh concerns for energy markets and supply security.
In its Tuesday report, the Paris-based agency said maintaining stable output now requires far greater investment, as nearly 90% of upstream spending already goes into offsetting losses rather than meeting new demand.
The IEA’s analysis, based on data from 15,000 fields, shows conventional oil output drops by an average of 5.6% annually, while gas production falls by 6.8% once fields hit peak output.
Without continued investment, global oil supply would shrink by 5.5 million barrels per day each year—equivalent to the combined output of Brazil and Norway—compared with around 4 million barrels lost annually in 2010.
Natural gas losses are also accelerating, rising to 270 billion cubic meters annually from 180 bcm a decade ago.
The warning comes as the IEA faces criticism from the United States and OPEC over its 2021 recommendation to halt new oil, gas, and coal projects in pursuit of climate targets.
OPEC countered the latest findings, arguing that the IEA’s earlier forecasts of peak oil demand by 2030 discouraged vital investment and created uncertainty across the industry.
IEA Executive Director Fatih Birol stressed that decline rates are the “elephant in the room” for the energy sector, emphasizing that accelerated losses must be addressed through timely and sustained funding.
The standoff highlights the widening policy divide between clean energy transition advocates and oil producers who insist that investment in fossil fuels remains critical to meeting demand and avoiding market instability.