Gold bars are on display at Korea Gold Exchange in Seoul's Jongno District, July 1. Yonhap

The Bank of Korea (BOK) said Thursday that it holds more than $250 million worth of a gold exchange-traded fund (ETF) traded on the U.S. stock market, marking its first investment in gold in 13 years.

In a filing with the U.S. Securities and Exchange Commission (SEC), the BOK said it held 679,765 shares of SPDR Gold Trust, one of the most widely traded gold ETFs in the United States, worth $250.4 million as of the end of the second quarter.

Gold ETFs provide investors with exposure to gold by tracking changes in the price of the precious metal, allowing them to benefit from gold price movements without owning the physical asset.

The BOK did not elaborate on the exact timing of the ETF purchase, but the holding was not included in its filing at the end of the first quarter.