SEOUL - South Korean billionaire Brian Kim, founder of the country's leading chat app operator Kakao Corp, stepped down from its board to focus on global expansion of its affiliates' businesses, the company said on Monday.

Kim will focus on Kakao-backed Piccoma in Japan, one of the country's top comics apps, as a base to seek more business opportunities and expand Kakao's reach, the app operator said in a statement.

A Kakao affiliate acquired two U.S. storytelling apps for $950 million last year for global expansion, after its success with online-based web cartoons or "webtoons" at home and in overseas markets led Piccoma to become one of Japan's highest-grossing mobile apps outside games.

The move comes after Kakao's financial services affiliate Kakao Pay Corp saw its chief executive officer and two other executives step down amid fierce criticism of their exercising of stock options soon after the firm listed last November.

Shares in Kakao rose up to 3.4% during Monday trade, versus a 0.5% drop in the wider market.

  - Reuters