Ray Dalio believes the United States is going to have a debt crisis and is closely watching the "risky" fiscal situation, CNBC reported Thursday, citing an interview with the billionaire investor.

"How fast it transpires, I think, is going to be a function of that supply-demand issue, so I'm watching that very closely," said Dalio, founder of hedge fund Bridgewater Associates, in the interview.

The country's debt has been under the spotlight in recent months after political brinkmanship around the debt limit earlier this year brought the U.S. close to a default.

Though the situation was averted, such partisan conflicts could hurt the country's fiscal reputation, analysts have said.

In August, rating agency Fitch downgraded U.S. credit rating by a notch from the top tier, citing fiscal deterioration over the next three years and repeated down-the-wire debt ceiling negotiations.

A looming government shutdown could further add to the country's pain. Earlier this week, Fitch's peer Moody's said a government shutdown would harm the country's credit in a stern warning.