U.S. tech giant Apple Inc. is set to release its first smartwatch in the South Korean market later this week, facing off with its archrival Samsung Electronics Co. in the wearable device segment, industry sources said Thursday.

Released in the United States in April, the Apple Watch has been gathering popularity abroad, with industry tracker Slice Intelligence claiming the sales reached 2.79 million units through June, emerging as a threat for Samsung who tapped the smartwatch market in 2013.

Industry sources said while Samsung has since released six different models, the combined sales is estimated at only around 2 million units.

Samsung has been suffering a slump in its revenues over past quarters, as Apple's iPhone lineup weighed down its high-end sector, while Chinese players ate into its lower segments.

Samsung earlier said that it plans to release its first round smartwatch, but it is yet to provide a detailed launch schedule, thus giving Apple the upper ground in the local market.

Samsung's smaller local rival LG Electronics Inc., which takes up around 15 percent of the domestic market, released its LG Watch Urbane lineup earlier this year. (Yonhap)