LONDON—The dollar was edging higher on Wednesday and headed for its biggest monthly gain since September and while the yen was set for its sharpest monthly drop in almost a year, as traders waited on a U.S. rates decision to round out January.
The dollar index has gained 2.1 percent against a basket of major currencies this month as markets dialled back expectations on the speed and scale of U.S. rate cuts in the face of strong economic data and pushback from central bankers.
