First-quarter corporate investment increased compared to last year, but it was mainly due to a handful of top conglomerates, pointing to a growing imbalance between big and smaller companies, data indicated Sunday.

Analysis by corporate watcher CEO Score showed South Korea's top 30 business groups invested 20.5 trillion won ($20.06 billion) in the first quarter of this year, roughly 9 percent more than the same period last year.

But excluding Samsung, which increased its investment by 48 percent, the amount is actually 4 percent less than last year.

Excluding the top five business groups, corporate investment fell 13 percent, data showed.

Grappling with slowing consumption from April's deadly ferry sinking, the government is urging companies to expedite their investment and spur hiring to revive the local economy.

Data showed companies invested more in tangible assets, including factories and facilities, increasing the amount by 13 percent to 16.4 trillion won. Investment in non-tangible assets decreased 3.4 percent to 1.98 trillion won.

Samsung Group, the nation's biggest conglomerate, spent 6.83 trillion won, 91 percent of which was by Samsung Electronics who allocated the investment to chip-making and display production facilities. The amount spent by the group accounts for one-third of the total investment by the top 30 conglomerates.

SK Group came next, spending 2.79 trillion won in the first quarter. About half of it was used to upgrade assembly lines for memory chips at its affiliate SK hynix.

LG and Hyundai Motor spend a comparable 2.7 trillion won and 2.2 trillion won, respectively, both about 12 percent less than the same period last year, data showed. (Yonhap)