The United States will become the world’s largest oil producer by around 2020, temporarily overtaking Saudi Arabia, as new exploration technologies help find more resources, the International Energy Agency forecast on Monday.

In its World Energy Outlook, the energy watchdog also predicted that greater oil and natural gas production — thanks partly to a boom in shale gas output — as well as more efficient use of energy will allow the U.S., which now imports some 20 percent of its energy needs, to become nearly self-sufficient around 2035.