SEOUL - South Korea's business sentiment edged up this month, but the figure stayed at a low level due to lingering economic uncertainties and weak domestic demand, data by the central bank showed Thursday.

The monthly business survey index (BSI), which gauges local manufacturers' assessment of current business conditions, stood at 72 in August, up 1 point from a month earlier, according to the Bank of Korea (BOK). The seasonally-adjusted figure rose 2 points to 70 over the same period.

The August figure rebounded for the first time in four months, but it stayed at a low level, indicating that local companies still worried about economic uncertainties at home and abroad as well as still fragile domestic demand.

Meanwhile, the BSI for September, measuring manufacturers' outlook on business conditions for the upcoming month, jumped 5 points on-month to 75, posting the first gain in four months. The reading adjusted with seasonal factors advanced 4 points to 73 over the cited period.

Local manufacturers listed uncertain economic conditions, weak domestic demand and sluggish exports as major difficulties in doing business.

The monthly index for non-manufacturers declined 1 point on- month to 66 in August, but the index for September stayed unchanged at 69 from the previous month, according to the BOK.

Non-manufacturers picked fragile domestic demand, economic uncertainties and fiercer competition as their hardship.

The BSI index is based on a nationwide survey of 1,424 manufacturers and 1,010 non-manufacturers, conducted between Aug 16 and 23.

Meanwhile, the economic sentiment index (ESI), which reflects both the consumer sentiment index (CSI) and the BSI, declined 2 points on-month to 90 in August.

The BOK started compiling the ESI from June in a bid to offer comprehensive sentiment of the private sector, including consumers and businesses.

The reading below 100 means the private sector's sentiment over the current economic conditions is weaker than the long-term average sentiment in the past.