Japanese shares ended lower as cautious investors refrained from placing big bets ahead of meetings by the U.S. Federal Reserve and other central banks, while the spread of the Omicron coronavirus variant also dented risk appetite globally. The Nikkei (.N225) closed 0.73% lower at 28,432.64, while the broader Topix (.TOPX) gave up early gains to end 0.22% weaker at 1,973.81. "Caution grew among investors as lesser time remained until they hear the outcome of the FOMC meeting, which could set a path for accelerated tapering and rate increase," said Kentaro Hayashi, senior strategist at Daiwa Securities, referring to the Federal Open Market Committee. "Monetary tightening brings headwinds for the stock market." The U.S. Fed on Wednesday is expected to signal a faster wind-down of asset purchases, while the European Central Bank, the Bank of England and the Bank of Japan will also meet to discuss normalizing their own monetary policies. Wider Asian equities also declined after British Prime Minister Boris Johnson warned of a "tidal wave" of new Omicron cases, and the World Health Organization said it poses a "very high" global risk. Index heavyweights declined, with Uniqlo clothing shop owner Fast Retailing (9983.T) losing 2.72%. Chip-related Tokyo Electron (8035.T) fell 1.83% and air-conditioning maker Daikin Industries (6367.T) slipped 1.24%. Travel-related stocks took a hit after news that the fast-spreading Omicron variant accounted for around 40% of infections in London and at least one death in the United Kingdom. read more Airlines (.IAIRL.T) and railways (.IRAIL.T) led declines in the Japanese bourse"s 33 industry sub-indexes, with ANA Holdings (9202.T) losing 1.97%, Japan Airlines (9201.T) falling 2.82% and Central Japan Railway (9022.T) slipping 1.38%. The insurance sector (.IINSU.T), up 1.57%, was the best performer, followed by drugmakers (.IPHAM.T), which rose 0.97%. Auto and parts makers (.ITEQP.T) also gained, with Toyota Motor (7203.T) rebounding from previous session"s losses with a 2.15% climb and Honda Motor (7267.T) advancing 0.6%. Editing by Sherry Jacob-Phillips Our Standards: The Thomson Reuters Trust Principles.