South Korea's economy picked up momentum in the first quarter due to increased construction and consumer spending, the central bank said Thursday.

The economy grew 0.8 percent on-quarter in the January-March period, up from a revised 0.3 percent growth in the previous quarter, the Bank of Korea said.

From a year earlier, the fourth-largest Asian economy expanded 2.4 percent.

The central bank has already cut its 2015 growth forecast twice this year, from 3.9 percent to 3.4 percent in January and down again in April to 3.1 percent.

In April, it held its key interest rate at a record low of 1.75, following a 25 basis point reduction the previous month.

Construction made a turnaround from a 7.8 percent contraction in the fourth quarter of 2014 to a 7.5 percent expansion in the January-March period on increased residential building projects.

In a bid to bolster the sagging economy, the government eased restrictions on housing loans last year.

In contrast, facility investment and exports remained flat.