Federal Reserve Chairman Jerome Powell said the central bank's long-awaited program to lend to small- and medium-sized businesses is about to get off the ground.

The Main Street lending facility, which will target companies with up to 15,000 employees, has been difficult to set up but is just about ready, Powell told Princeton University economist and former Fed official Alan Blinder in a webinar interview Friday.

"We're days away from making our first loans in Main Street,” he said. "We have three facilities that are part of it. They're meant to reach out to different parts of that broad space. In the meantime, many of those companies are finding that they can borrow from banks. Others are waiting for us to get our facilities up and running.”

"It is far and away the biggest challenge of any of the 11 facilities that we've set up,” he added.

Source : CNBC