Global credit rating agency Fitch Ratings says Europe’s debt crisis poses a “serious risk” to U.S. banks.

Fitch said in a report released Wednesday that the credit outlook for the U.S. banking industry could worsen unless the contagious euro zone debt crisis is resolved in a timely and orderly manner.

The agency said the U.S. banking industry is keeping an eye on its credit level, which is currently at a “stable” level. But it added that the outlook may change in the future, as the negative effects of the European crisis are growing.

Fitch said although U.S. banks cut direct investments in the European market last year, the euro zone crisis still poses a serious risk.