S.Korea shares hit record high in longest weekly rally since mid-2017

* KOSPI rises, foreigners net buyers

* Korean won strengthens against U.S. dollar

* South Korea benchmark bond yield rises

* Samsun Electronics soars near 7%

* For the midday report, please click

SEOUL, Dec 24 (Reuters) - Round-up of South Korean financial markets: ** South Korean shares closed up at a record high on Thursday, posting their longest weekly rally in 3-1/2 years, as a likely Brexit trade deal soothed investors in thin trading ahead of Christmas holidays. The won strengthened, while the benchmark bond yield rose. ** By 06:33 GMT, the benchmark KOSPI rose 47.04 points, or 1.70%, to 2,806.86. For the week, the index logged an eighth straight gain, its longest weekly rally since mid-2017.

** The South Korean market is closed on Friday for Christmas.

** Samsung Electronics shares soared 5.3%, after jumping as much as 6.6% to hit a record high earlier in the session. ** Britain and the European Union appeared close to clinching a long-elusive trade agreement on Wednesday. ** South Korea signed deals with Pfizer Inc and Johnson & Johnson’s Janssen to import coronavirus vaccines to cover up to 16 million people, as it grapples with the third wave of infections.

** Foreigners were net buyers of 111.4 billion won ($101.14 million) worth of shares on the main board. ** The won was quoted at 1,103.0 per dollar on the onshore settlement platform, 0.44% higher than Wednesday’s close at 1,107.9. But the local currency posted its third weekly drop. ** In offshore trading, the won was quoted at 1,101.9 per dollar, up 0.4% from the previous day, while in non-deliverable forward trading its one-month contract was quoted at 1,100.1. ** The KOSPI has risen 27.72% so far this year, gaining 11.0% in the previous 30 trading sessions, while the won has gained 4.8% against the dollar. ** In money and debt markets, March futures on three-year treasury bonds fell 0.07 points to 111.56. ** The most liquid 3-year Korean treasury bond yield rose by 1.8 basis points to 0.950%, while the benchmark 10-year yield rose by 4.1 basis points to 1.681%. ($1 = 1,101.4400 won) (Reporting by Cynthia Kim; Editing by Rashmi Aich)