Ford Motor Company's (F 0.66%) credit rating was downgraded by Fitch Ratings on Monday, a move that puts Ford's hard-won investment-grade rating in peril. 

Fitch cut Ford's credit rating by one notch, to BBB-, with a "negative" outlook. The rating applies to both Ford Motor Company itself as well as its financial-services subsidiary, Ford Credit. BBB- is the lowest level considered "investment grade." 

Fitch said that the downgrade "reflects Fitch's significant concerns about the effect that the global coronavirus mitigation actions currently under way will have on the company's near-term financial performance and credit profile."

Ford's world headquarters building in Dearborn, Michigan.

Image source: Ford Motor Company.

Fitch said that it believes Ford has ample financial flexibility to get through an extended shutdown of its factories in North America and Europe. The agency's concern is with what could happen afterward: If COVID-19 passes but leaves Europe and North America mired in deep recessions that could strain Ford's balance sheet and lead to a further downgrade. 

On the other hand, if Ford's operations return to a "typical run rate" in the second half of 2020, it could revise the company's outlook to "stable," Fitch said.

The downgrade puts Ford's investment-grade rating in peril. Moody's Investors Service cut Ford's rating to junk level in September; if either Fitch or the third credit-rating agency, Standard & Poor's, follows suit, then Ford will no longer be considered an investment-grade credit. 

Ford suspended production at its factories in North America and Europe until at least the end of March, to sanitize the facilities and to adjust its inventories ahead of an expected sales decline. 

Ford last week drew down $15.4 billion from its credit line and suspended its dividend.