S.Korea stocks gain on upbeat trade data, Biden's infra plan

* KOSPI rises, foreigners net buyers

* Korean won weakens against U.S. dollar

* South Korea benchmark bond yield falls

* For the midday report, please click

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

** South Korean shares ended higher on Thursday, driven by gains in chip heavyweights and foreign buying, as a double-digit expansion in exports and hopes that the U.S. President Joe Biden’s infrastructure plan will boost recovery lifted investor sentiment.

** The won was nearly unchanged, while the benchmark bond yield fell.

** The KOSPI closed up 25.98 points, or 0.85%, at 3,087.40, rebounding from a 0.28% fall on Wednesday.

** The nation’s exports in March expanded for a fifth straight month and by 16.6% year-on-year, thanks to robust demand for chips and petrochemical products.

** On the heels of a $1.9 trillion pandemic relief package, U.S. President Joe Biden on Wednesday outlined a broad $2 trillion proposal to re-make the world’s biggest economy including spending on roads, railways, broadband, clean energy and semiconductor manufacture.

** Chip heavyweights Samsung Electronics and SK Hynix jumped 1.84% and 6.04% each, leading the benchmark gains, while battery maker LG Chem and internet giant Naver also added 1.74% and 0.40%, respectively.

** Foreigners were net buyers of 562.6 billion won ($497.19 million) worth of shares on the main board.

** The won ended at 1,131.9 per dollar on the onshore settlement platform, 0.01% lower than its previous close at 1,131.8.

** In offshore trading, the won was quoted at 1,131.8 per dollar, down 0.4% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,131.9.

** In money and debt markets, June futures on three-year treasury bonds was unchanged at 110.79.

** The most liquid 3-year Korean treasury bond yield rose by 0.9 basis points to 1.142%, while the benchmark 10-year yield fell by 1.9 basis points to 2.038%. ($1 = 1,131.5700 won) (Reporting by Joori Roh; Editing by Rashmi Aich)