Major South Korean companies are expected to increase their capital expenditures by nearly 15 percent in 2015 from last year despite the economy's prolonged weakness, a state bank said Sunday.

A survey on 2,500 manufacturing and service companies shows that the businesses plan to spend a combined 157.3 trillion won ($141 billion) on new plants and equipment this year, up 14.9 percent from last year, according to the Korea Development Bank.

Excluding one-off investments like Hyundai Motor Group's purchase of a prime land lot in southern Seoul, the total stands at 146.8 trillion won, representing a 7.2 percent increase from 2014.

Hyundai Motor Group, the world's fifth-largest automaker, agreed to buy the land for 10.5 trillion won from state power company Korea Electric Power Corp. and plans to build a new main office there.

According to KDB, large companies' capital expenditures are likely to increase 16.2 percent in 2015 from last year, while investments by small and medium enterprises are projected to sink 11 percent.

Capital spending by manufacturing companies is forecast to shoot up 18.3 percent on-year in 2015, with the nonmanufacturing sector's facility investments projected to grow 11 percent.

Last year's actual facility investments totaled 136.9 trillion won, up 5.1 percent from the previous year, according to the bank. (Yonhap)