New York Federal Reserve President John Williams believes low inflation is one of the biggest bears threatening the U.S. economy in this era, and he’s ready to use monetary policy to fight it off and sustain economic expansion.

“Low inflation is indeed the problem of this era. The current outlook of moderate growth, low unemployment but stubbornly low inflation is a reflection of the broader economic picture,” Williams said in a speech Wednesday. “I am carefully monitoring this nuanced picture and remain vigilant to act as appropriate to support continuing growth, a strong labor market and a sustained return to 2% inflation.”

Williams pointed out other countries’ ominous struggles while the U.S. faces its own issues surrounding the ever-escalating trade war with China.

“Germany, the UK, and China are all experiencing slowdowns, and the euro area is of particular concern,” Williams said. “On our own shores, concerns around trade policy with China are adding to an uncertain picture. My contacts in the business community have said this is making them more cautious about investment. The effects of this angst are already showing up in the investment numbers.”

The Federal Open Market Committee will meet again Sept. 17-18, and another rate cut is expected to come out of the meeting. The Fed cut its key policy interest rate by 25 basis points to a range of 2% to 2.25% during its July meeting. Williams pointed to slowing growth and flailing inflation as the main drivers behind the decision for the rate cut.

“While there’s not been a dramatic change seen in the overall numbers yet, the more detailed picture that emerged by summer of this year pointed to an outlook of slowing growth and inflation falling short of our goal,” Williams said. “This in turn argued for a somewhat more accommodative monetary policy stance.”

The Fed is seemingly split on whether further rate cuts are necessary, and Williams wouldn’t reveal what stance he is taking during the September meetings. Back in July, Williams argued that central bankers should act quickly to prevent slower growth, saying “it’s better to take preventative measures than to wait for disaster to unfold.”

The CME FedWatch tool is projecting a 92.7% chance of a 25 basis points interest rate cut, and a 7.3% chance of a 50-basis-point cut.