The currency swap deal marks the second of its kind to be signed between South Korea and the US
The BOK said the country supplied a total of $16.4 billion under its first currency swap agreement worth $30 billion.
The country supplied $4 billion in the first batch of installments under the 2008 agreement, the official noted.
"This time, we plan to supply a much greater amount in the first installment," he said.
South Korea has increasingly been facing a dollar shortage amid a market rout triggered by the spread of COVID-19.
The Korean won closed at 1,249.60 won per dollar Tuesday, down 91.5 won, or 7.9 percent, from the closing rate of 1,158.10 won per dollar on Jan. 20, when South Korea reported its first confirmed case of the viral disease.
South Korea has bilateral currency swap arrangements, worth more than $193 billion in total, with eight other countries, including Australia, Canada and China.
It also holds the world's ninth-largest foreign exchange reserves, which stood at $409.17 billion at end-February, according to the BOK. (Yonhap)