National Economic Council Director Kevin Hassett, a top economic advisor to Trump, on Monday rebuked concerns about tariff-related inflation. The Fed, Hassett told CNBC, has been "very, very wrong" in its assessment of a potential resurgence of price increases.

New data showing price increases last month could foreshadow even higher costs if the president imposes steep tariffs on Aug. 1.

Critics of President Trump's tariff policies have been waiting for the import taxes to raise the inflation rate. That effect may be beginning.