* Takes 4.3% stake in Hanjin Kal, to move to 10% over time
* Hanjin Kal targeted by activist fund
* Delta wants to ensure stable management - Korean Air (Adds Hanjin Kal, Korean Air share reaction)
CHICAGO/SEOUL, June 20 (Reuters) - Delta Air Lines Inc said on Thursday it had acquired a 4.3% stake in joint-venture partner Korean Air Lines Co Ltd's parent company with a view toward expanding across Asia.
Atlanta-based Delta is growing internationally both through joint ventures - which allow airlines to coordinate fares and schedules while building a presence in new markets - and equity investments, which help airlines align their respective strategies.
The No. 2 U.S. carrier said it intended to increase its stake in Hanjin Kal Corp, which owns about 30% of Korean Air, to 10% over time, after receiving regulatory approval.
It did not disclose how much it paid for the 4.3% stake, worth about $88 million, according to current market prices.
Delta's stake purchase was intended to ensure its partner's "stable management rights," Korean Air said in a statement.
Hanjin Kal shares fell as much as 7.1% on Friday. Korean Air fell 1.4 percent and its budget affiliate Jin Air Co Ltd rose 0.2 percent in the wider market that was down 0.2% as of 1225 GMT.
Delta has said it sees Seoul's Incheon International Airport, the hub of Korean Air, as a gateway for more destinations across Asia.
The two airlines are members of the SkyTeam alliance and formed a joint venture last year that includes 290 U.S. destinations and over 80 in Asia. This year, Delta launched routes to Seoul and Osaka in partnership with Korean Air, Hanjin Kal's flagship unit.
"Long term, the partnership and the joint venture is strong in terms of size and there's no reason to think it can't grow substantially into the future," Delta Chief Executive Ed Bastian said at an aviation summit earlier this month in Seoul.
Delta also owns stakes in Grupo Aeromexico, Air France KLM, China Eastern, Brazil's Gol and Virgin Atlantic, and has been negotiating a stake in Alitalia.
KOREAN AIR SUCCESSOR
Delta's investment follows the sudden death in April of Cho Yang-ho, the patriarch of Hanjin Kal and Korean Air, which raised questions about the future of both.
Since the death of his father, 43-year-old Walter Cho has led Korean Air as CEO and chairman, but the company has yet to inform regulators about a definitive succession plan.
The late tycoon died at age 70, just weeks after shareholders decided to end his 27-year tenure on the airline's board. Cho's widow, two daughters and Walter Cho all hold stakes in Hanjin Kal.
At the Seoul conference, Bastian said he had "a lot of confidence" in Walter Cho, noting their friendship had gone back 20 years.
Hanjin Kal's ownership structure has come under scrutiny since a local activist fund raised its stake to nearly 16%. The Cho family and its academic foundations own 29%, including the late Cho's 17.8% stake.
If Delta raises its stake to 10% in Hanjin Kal, with diversified businesses including hotels, logistics and budget airlines, it would become the third biggest shareholder.
Korean Air grows its own food for cabin meals and also owns hotels and a limousine service
Shares in Delta closed down 0.7% at $55.97 in New York on Thursday. (Reporting by Tracy Rucinski in Chicago and Hyujoo Jin in Seoul; Additional reporting by Rachit Vats in Bengaluru, Ju-Min Park in Seoul and Jamie Freed in Singapore; Editing by G Crosse, Peter Cooney and Muralikumar Anantharaman)