The capital adequacy ratio of South Korean bank holding companies fell in the first quarter of this year from three months earlier, largely due to a decrease in the amount of capital set aside to counter risk, the financial regulator said Thursday.

The average capital adequacy ratio of 10 local bank holding companies, including top player Woori Finance Holdings Co., stood at 13.11 percent as of the end of March, down 0.12 percentage point from three months earlier, according to the Financial Supervisory Service.

Compared with the previous year, the figure climbed 0.2 percentage point from 12.91 percent, the FSS said.

The on-quarter decline came as the bank holding firms saw their capital buffers shrink as their subordinated bonds reached maturity, the watchdog noted.

The capital buffer refers to the minimum amount of capital required by the Basel II capital rules, in which a bank must set aside as provisions against capital risks.

But their core capital, otherwise known as Tier 1 capital, stayed nearly steady at 10.49 percent, compared with 10.47 percent over the cited period.

The core capital, a key gauge of a bank’s financial strength, consists of common stock and retained earnings.

Citibank Korea Inc. topped other rivals with its capital adequacy ratio coming in at 17.15 percent, followed by Standard Chartered Bank Korea at 16.47 percent, largely due to a decrease in risk-weighted assets. (Yonhap News)