South Korea's exports are expected to continue to log double-digit growth for a while on the back of steady overseas demand for semiconductors, global market research firm Moody's said Sunday.

"We expect annual export growth to keep rising at a double-digit pace thanks to the sustained uptick in the tech cycle lifting shipments of semiconductors and machinery," Moody's said in its weekly report. "South Korea's monthly trade surplus likely narrowed to $9.8 billion in July, from $11.4 billion in June."

Outbound shipments by Asia's fourth-largest economy have been rising since November last year on an upturn in world trade. The recent gains are in sharp contrast to the 8 percent drop in 2015 and 6 percent fall in 2016. The negative growth was caused by a decline in oil prices that dampened demand from resource-rich emerging countries.

During the first six months of 2017, South Korea's exports grew by double digits every single month as booming demand for computer chips and machinery pushed up overall trade numbers.

Exports of semiconductors soared nearly 50 percent on-year to reach a record $42.9 billion in the six months through June, while shipments of machinery also jumped 11.7 percent to an all-time high of $24.2 billion.

But Moody's noted the pace will likely slow down starting in the third quarter amid diminishing overseas sales of new mobile devices.

"We expect exports to cool towards the end of the September quarter as new releases, especially for smartphones, fade," it said.

The South Korean government will release the latest data for July exports and imports on Tuesday next week. (Yonhap)