The esteemed investor said in an interview with CNBC that he couldn’t deny the economy was strong, but that it was actually “on steroids” owing to massive government spending and borrowing.

“We’ve got a 6% to 7% budget deficit. We’re fast-pouring consumption like crazy,” Jones told CNBC.

The Commerce Department reported last month that the U.S. economy grew 3.1% in 2023, a better-than-expected performance that surprised some doomsaying analysts. At the same time, the U.S. deficit essentially doubled in 2023 to $1.7 trillion. So far this year, the national debt has surpassed $34 trillion, equivalent to 123% of total economic output in the U.S. And that’s set to grow even more: The Congressional Budget Office projected Wednesday that the deficit could grow to $2.6 trillion, or about 6% of U.S. GDP, over the next 10 years.

Jones is not the only one to call attention to the growing deficit issue in the U.S. On Sunday, Federal Reserve Chairman Jerome Powell took a rare dive into politics, telling CBS’s 60 Minutes that the national debt was “growing faster than the economy,” and calling for lawmakers to get the federal government “back on a sustainable fiscal path.”

Meanwhile, U.S. Treasury Secretary Janet Yellen has said she is not yet worried about the increasing national debt as long as the government keeps in check the net payments it makes on its debt relative to GDP. Those payments are projected to rise from 2.5% last year to 2.9% next year, according to the Office of Management and Budget—below their level in the early 1990s.

Jones told CNBC that the strong economy could postpone the effects of the government’s deficit spending, but only for a little while. 

“The only question is … when does that manifest itself in markets?” he added. “It could be this year, it could be next year. Productivity may mask and it might be three or four years from now. But clearly, clearly we’re on an unsustainable path.”