A money changer counts U.S. dollar banknotes at a currency exchange office in Ankara, Turkey.

The dollar gained on the euro on Thursday before key U.S. inflation data due on Friday and as investors squared positions for month- and quarter-end.

The Japanese currency was also modestly weaker at 151.39 per dollar having traded just shy of the 152 mark at its weakest since 1990 on Wednesday before Japan's top monetary officials suggested they were ready to intervene to prevent further declines.