SEOUL - South Korea's central bank said on Thursday it will conduct outright purchases of treasury bonds worth 1.5 trillion won ($1.23 billion) to stabilise the bond market.

"The Bank of Korea plans to carry out outright purchase of treasury bonds to improve the supply and demand conditions in the bond market through the expansion of bond purchasing capacity of financial institutions," it said in a statement.

The bank also said it will target three different maturities, the 5-, 10-, and 20-year, in its auction to take place on Friday.

($1 = 1,217.1700 won)

(Reporting by Joori Roh; Editing by Himani Sarkar) ((joori.roh@thomsonreuters.com; +82 2 6936 1493;))