Foreigners have continued to expand investment in the South Korean bond market this year despite heightened geopolitical risks from North Korea's nuclear programs, the finance ministry said Thursday.

Foreigners have made a net investment of 6.2 trillion won ($5.6 billion) in the bond market here so far this year, bringing their total bond holdings to 97.4 trillion won as of end-April, according to a report by the ministry.

Foreign investment made up 7.2 percent of the total outstanding Korean bonds, slightly up from 7 percent tallied at the end of 2012, the report showed.

Foreign investors appear to prefer longer-term Treasuries to monetary stabilization bonds this year.

Foreigners held 16.3 percent of outstanding Treasuries as of end-April, up from December's 15.7 percent. The ratio for monetary stabilization bonds stayed almost unchanged at 19.7 percent, the report showed.

The ministry said that foreign capital keeps flowing into the bond market this year despite heightened geopolitical risks stemming from the North's repeated war rhetoric in recent months.

"The government will continue its close monitoring of the foreign investment trend, while making efforts to maintain stable flows (of foreign capital)," a ministry official said. (Yonhap News)