A Chinese bank employee counts 100-yuan notes and U.S. dollar bills at a bank counter in Nantong in China's eastern Jiangsu province on August 6, 2019.

Chinese corporate debt is the "biggest threat" to the global economy, warned a Moody's Analytics economist, who described such risks as a "very significant fault line."

That followed similar comments by Fitch Ratings last week, which said that private companies in China have defaulted on their debts at a record pace this year.

While corporate debt is a "fault line in the financial system and the broader economy," Moody's Chief Economist Mark Zandi flagged indebted Chinese companies as the larger risk.

"I would point to Chinese corporate debt as the biggest threat," he said, adding that it's growing very rapidly in China.

Zandi explained that many companies are struggling to deal with a slowdown in growth stemming from the trade war and other factors.

"In the United States, it's similar kind of picture — not to the same degree — but we have seen very significant increase in so-called leveraged lending, as in lending to highly indebted companies, and they are vulnerable if the economy were to slow," Zandi said.

Debt has been a problem in the world's second largest economy, which has been trying to reduce its reliance on it by tightening regulations to speed up deleveraging — or the process of reducing debt.