* KOSPI rises, foreigners net buyers

* Korean won strengthens against U.S. dollar

* South Korea benchmark bond yield rises

* For the midday report, please click

SEOUL, Feb 1 (Reuters) - Round-up of South Korean financial markets: ** South Korean shares posted their biggest daily gain in about three weeks on Monday, as upbeat January exports data lifted sentiment, while volatility concerns around U.S. retail investors receded. The won strengthened, while the benchmark bond yield rose. ** By 06:32 GMT, the benchmark KOSPI rose 80.32 points, or 2.70%, to 3,056.53, marking the biggest daily gain since Jan. 8. ** January exports jumped 11.4% to $48.01 billion, government data showed, beating the 9.8% forecast in a Reuters survey.

** Shares are rebounding from last week's dip as positive trade data is reassuring investors that the recovery momentum is positive, says Lee Jae-sun, an analyst at Hana Investment & Securities.

** An army of retail investors that routed Wall Street's professionals in recent days was dealt a blow last week, after online brokerages restricted purchases of red-hot GameStop and other stocks.

**A swarm of online traders in South Korea is taking a leaf from the Reddit horde in the United States to quash a government plan to lift a pandemic-imposed ban on short-selling, triggering a rally in the most shorted-stocks such as Celltrion on Monday.

** Shares of Celltrion closed up 14.51%, Samsung Electronics gained 1.22%

** Foreigners were net buyers of 131.4 billion won ($117.67 million) worth of shares on the main board. ** The won was quoted at 1,116.5 per dollar on the onshore settlement platform, 0.21% higher than its previous close at 1,118.8. ** In offshore trading, the won was quoted at 1,116.1 per dollar, up 0.1% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,115.9. ** MSCI's broadest index of Asia-Pacific shares outside Japan was down 1.37%,. ** The KOSPI has risen 6.37% so far this year, and gained 8.0% in the previous 30 trading sessions. ($1 = 1,116.6700 won) (Reporting by Cynthia Kim; Additional reporting by Jihoon Lee; Editing by Rashmi Aich)