The chart of the week highlights countries with the largest proven oil reserves in 2025, led by Venezuela and Saudi Arabia, underscoring how oil supply remains highly concentrated in a small group of nations. While Venezuela tops the list by reserves, its ability to meet global oil demand is constrained by infrastructure challenges, sanctions, and underinvestment, limiting actual supply to the market. Saudi Arabia’s large reserve base, combined with spare production capacity, gives it outsized influence over short-term supply and global oil prices through OPEC+ decisions. Canada, Iran, and Iraq also play critical roles, though geopolitical risks and production costs shape how much of their reserves can be economically supplied. The United States, despite smaller reserves than many peers, remains a key driver of global supply due to shale production responding quickly to price signals and demand changes. Overall, global oil demand is met not just by who has the most oil underground, but by who can reliably produce, export, and scale supply in response to economic and geopolitical forces.