* KOSPI falls, foreigners net sellers

* Korean won weakens against U.S. dollar

* South Korea benchmark bond yield falls

* For the midday report, please click

SEOUL, Jan 24 (Reuters) - Round-up of South Korean financial markets:

** South Korean shares posted their biggest drop in five weeks on Monday, as investors weighed concerns about U.S. Federal Reserve tightening monetary policy and a possible Russian attack on Ukraine. The Korean won weakened, while the benchmark bond yield fell.

** The benchmark KOSPI fell 42.29 points, or 1.49%, to close at 2,792.00.

** Among the heavyweights, technology giant Samsung Electronics fell 0.66% and peer SK Hynix was flat, while LG Chem fell 3.31% and Naver fell 1.35%.

** Uncertainty over the pace of U.S. monetary policy tightening and a sharp decline in Wall Street shares on Friday hit Korean stocks, while geopolitical tensions in Eastern Europe also added to worries, said Lee Kyoung-min, analyst at Daishin Securities.

** Foreigners were net sellers of 435.6 billion won ($364.32 million) worth of shares on the main board.

** The won was quoted at 1,196.1 per dollar on the onshore settlement platform, 0.18% lower than its previous close at 1,194.0.

** In offshore trading, the won was quoted at 1,195.6 per dollar, down 0.3% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,196.1.

** The KOSPI has fallen 6.23% so far this year, but lost 6.4% in the previous 30 sessions.

** The trading volume during the session in the KOSPI index was 468.25 million shares. Of the total traded issues of 930, the number of advancing shares was 85.

** The won has lost 0.6% against the dollar so far this year.

** In money and debt markets, March futures on three-year treasury bonds rose 0.10 points to 108.20.

** The most liquid 3-year Korean treasury bond yield fell by 1.8 basis points to 2.114%, while the benchmark 10-year yield fell by 0.1 basis points to 2.539%. ($1 = 1,195.6400 won) (Reporting by Cynthia Kim; additional reporting by Jihoon Lee; editing by Rashmi Aich)