Buy-now-pay-later firm Afterpay Ltd APT.AX lost 3.3%. By Savyata Mishra Dec 15 (Reuters) - Australian shares ended lower on Wednesday as cautious investors refrained from placing big bets ahead of outcome of the U.S. Federal Reserve's two-day policy meeting, possibly adding to the pressure on its peers for further tightening. MKTS/GLOB The rapid spread of the Omicron variant is an added complication that could incline the Fed to be less hawkish, though recently officials have sounded more concerned about the persistence of inflation than the pandemic.