US central bankers remain divided over inflation risks, and some argue they can afford to "be patient" before raising rates again, according to the minutes of the last policy meeting released Wednesday.

The Federal Reserve had been expected to raise the benchmark lending rate a third time this year, but the minutes of the July 25-26 meeting showed policymakers remain befuddled by weak inflation, despite historically low unemployment.

The minutes also indicated the Fed could announce "relatively soon" the start of efforts to reduce the multi-trillion-dollar investment holdings.