Foreign currency deposits at South Korean banks rose to their highest level in June as companies put more money into them amid a wider trade surplus, the central bank said Thursday.

Foreign currency-denominated deposits held by residents reached an outstanding a record high of $33.48 billion as of the end of June, up $1.42 billion from the previous month, according to the Bank of Korea.

The term residents includes individual citizens, firms and foreign nationals who have lived in the country for more than six months.

Banks’ foreign currency deposits rose mostly on continued exports and concerns the won’s ascent may reverse in the near term.

The local currency appreciated 3.05 percent to the U.S. dollar in June from the previous month. The government in late June unveiled plans to encourage local banks to lure more foreign currency deposits in a bid to build a safety net from external shocks. (Yonhap News)