Oilman T. Boone Pickens said Thursday that Saudi production is topping out at about 10 million barrels per day and oil prices will return to $70 per barrel by the end of the year.
OPEC is "all in at 31 million barrels a day. That's about all they can do," Pickens said on CNBC's "Squawk Box." "They talk a lot about it, what they can do, and the Saudis say 12 and half. Well show me. I'm ready to see 12 and a half.They're making 10.3, and they struggle at 10, I think. I think 10 is about all the Saudis can do."
Oil Minister Ali al-Naimi said Saudi Arabia produced some 10.3 million bpd of crude in March, eclipsing a previous high of 10.2 million in August 2013.
The Organization of the Petroleum Exporting Countries is expected at a meeting on Friday to keep a group output target of 30 million bpd, a ceiling it has been exceeding for most of the last two years, weakening prices.
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The cartel is now pumping about 2 million bpd more than needed, analyst say, feeding a glut that has left millions of barrels stored on tankers without a buyer and kept prices at close to half their peak levels last year.
Production declines in the United States will also support prices, Pickens said, noting that output has dropped off in North Dakota's Bakken formation and Texas's Eagle Ford play as drillers have taken about 1,000 rigs out of oilfields since December.
"Now, you shut down 1,000 rigs, we're dealing with decline curve," said Pickens, chairman of BP Capital Management. "If you're trying to grow production, you've first got to maintain production."
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Oil wells—whether conventional or unconventional—reach peak production soon after they yield the first drop of crude. The U.S. industry is dominated by unconventional wells.
Conventional wells go through a long period of steady, flat production between peak and decline. In contrast, production falls rapidly in the first three years of unconventional wells—those in shale, sandstone and carbonates. They then enter a long phase of very low production.
"Just as soon as you get an oil well, put it on production, it starts to decline," Pickens said. "Now how fast is it going to decline is very important."
—Reuters contributed to this story.