South Korea's debt from bond issuance reached 765.6 trillion won (US$687.8 billion) this month, raising concerns over increasing tax burdens down the road, data showed Wednesday.

According to the data compiled by Korea Financial Investment Association, the combined amount of state bonds needing to be repaid by the South Korean government reached 436.1 trillion won on Monday, up 5.5 percent from the end of 2012.

The amount of special bonds, which refer to debt sales floated by state-owned enterprises, amounted to 329.4 trillion won, up 4.45 percent from 315.4 trillion won tallied in end-2012, the data added.

The combined amount hovers far above the country's annual budget for 2013, which came at 342.5 trillion won.

Governments tend to rely on bond issuance when securing funds needed for policy implementations, as it gives them more leeway than a tax increase, which may bring resistance.

Market watchers said, however, an excessive issuance of bonds may result in a heavier tax burden for future generations.

Meanwhile, the country's debt burden is anticipated to increase down the road as South Korea on Tuesday drew up an extra budget worth 17.3 trillion won for this year in a bid to revitalize its economy, market watchers added.

To finance the extra budget, the government plans to issue a total of 15.9 trillion won worth of bonds. The rest will be funded by using tax surplus from last year and other resources in a bid to minimize the debt sale, the government said. (Yonhap News)