* KOSPI falls, foreigners net sellers

* Korean won weakens against dollar

* South Korea benchmark bond yield rises

SEOUL, July 1 (Reuters) - Round-up of South Korean financial markets:

** The South Korean won weakened on Monday, with the dollar-won onshore market bracing for volatility as longer trading hours started. South Korean shares fell, while the benchmark bond yield rose.

** Dollar-won trading hours from Monday will be 9 a.m. to 2 a.m. (0000 GMT to 1700 GMT), compared to 9 a.m. to 3:30 p.m. (0000 GMT to 0630 GMT) earlier. ** The benchmark KOSPI fell 7.06 points, or 0.25%, to 2,790.76 by 00:58 GMT.

** Among index heavyweights, chipmaker Samsung Electronics rose 0.49% and peer SK Hynix lost 1.27%, while battery maker LG Energy Solution climbed 1.23%.

** South Korean exports increased for a ninth month in June, albeit at a slower pace than seen by analysts, as robust demand for chips continue to lead the export recovery in Asia's fourth-largest economy.

** Hyundai Motor shed 1.69% and sister automaker Kia Corp lost 0.46%, while search engine Naver and instant messenger Kakao fell 3.06% and 0.49%, respectively.

** Of the total 926 traded issues, 356 shares advanced, while 510 declined.

** Foreigners were net sellers of shares worth 69.1 billion won ($50.07 million).

** The won was quoted at 1,382.7 per dollar on the onshore settlement platform, 0.43% lower than its previous close at 1,376.7.

** In offshore trading, the won was quoted at 1,381.9 per dollar, down 0.1% on the day, while in non-deliverable forward trading its one-month contract was quoted at 1,379.1.

** The KOSPI has risen 5.10% so far this year, and gained 1.6% in the previous 30 trading sessions.

** In money and debt markets, September futures on three-year treasury bonds fell 0.12 point to 105.08.

** The most liquid three-year Korean treasury bond yield rose by 7.9 basis points to 3.222%, while the benchmark 10-year yield rose by 3.8 bp to 3.320%. ($1 = 1,380.0800 won)

(Reporting by Cynthia Kim; Editing by Rashmi Aich)