The tool is known as the countercyclical capital buffer, the WSJ reports. It allows the Fed to require banks to hold more capital should the economy show signs of overheating.

The tool was approved in 2016, but the Fed hasn’t used it so far.

According to WSJ "now, some Fed officials are debating whether it is time to use the tool, which could provide banks with additional lending firepower in a subsequent downturn. It isn’t clear when they might make a decision."