(Bloomberg) -- Federal Reserve Bank of Philadelphia President Patrick Harker said economic data in the coming weeks will help inform the appropriate magnitude of the US central bank’s first interest-rate cut.

“In September we need to start a process of moving rates down,” Harker said Thursday in a CNBC interview from Jackson Hole, Wyoming, ahead of the Kansas City Fed’s closely watched annual symposium there.

“We need to start bringing them down methodically,” Harker said. “Right now, I’m not in the camp of 25 or 50 — I need to see a couple more weeks of data,” he said, referring to a debate over whether the first cut should be 25 basis points or 50 basis points.

The Philadelphia Fed chief does not hold a vote on policy decisions this year.