Federal Reserve Chair Jerome Powell said the economic impact of new tariffs is likely to be significantly larger than expected, and the central bank must make sure that doesn’t lead to a growing inflation problem.

“While uncertainty remains elevated, it is now becoming clear that the tariff increases will be significantly larger than expected,” Powell said in prepared remarks Friday at the Society for Advancing Business Editing and Writing annual conference. “The same is likely to be true of the economic effects, which will include higher inflation and slower growth.”