KOSPI falls, foreigners net buyers Korean won weakens against U.S. dollar South Korea benchmark bond yield rises SEOUL, Jan 4 (Reuters) - Round-up of South Korean financial markets: ** South Korean shares fell on Tuesday, hurt by the dollar"s strength as traders bet on a more aggressive rate hike by the Federal Reserve, while higher cases of the Omicron coronavirus variant and preventive curbs dented sentiment further. ** The Korean won weakened to a 12-week-low, while the benchmark bond yield rose. ** By 0210 GMT, the benchmark KOSPI (.KS11) fell 12.33 points, or 0.41%, to 2,975.58, following a 0.37% gain on Monday. ** Among the heavyweights, technology giant Samsung Electronics (005930.KS) fell 0.13%, while platform company Naver (035420.KS) also dropped 2.53%. ** Money markets have fully priced in a first U.S. rate increase by May, and two more by the end of 2022, CME Group"s FedWatch program showed. ** Fears over the rapid spread of the Omicron variant led to preventive curbs in a number of businesses, including several major U.S. banks that encouraged staffs to work from home during the first few weeks of the year. read more ** That offset an overnight boost on Wall Street, which was driven by strong gains in Apple (AAPL.O) and Tesla (TSLA.O). ** China"s factory activity grew at its fastest pace in six months in December, a private survey showed, but that did little in aiding risk appetite. read more ** Foreigners were net buyers of 21.0 billion won ($17.58 million) worth of shares on the main board. ** The won was quoted at 1,194.9 per dollar on the onshore settlement platform , down 0.26%. ** In offshore trading, the won was quoted at 1,194.5, while in non-deliverable forward trading, its one-month contract was quoted at 1,195.1. ** In money and debt markets, March futures on three-year treasury bonds fell 0.08 point to 108.77. ** The benchmark 10-year yield rose by 3.8 basis points to 2.361%. ($1 = 1,194.5400 won)