SINGAPORE/HANOI -- Global investment firm KKR & Co has emerged as the largest shareholder of one of Vietnam's biggest eye hospital chains, Medical Saigon Group (MSG), according to an MSG internal memo seen by Reuters on Friday.

Financial details of the investment were not disclosed in the memo sent to MSG's staff on January 19 from MSG Group Chief Executive Officer Huynh Le Duc.

New York-based KKR will take over as MSG's largest shareholder from Singapore's investment firm Heliconia Capital, wholly-owned unit of Singapore's state investment firm Temasek Holdings, according to the memo.

Heliconia acquired MSG in 2019.

"KKR will step into the shoes of Heliconia to become our largest shareholder. Heliconia will transition out of MSG after a very successful partnership together," Duc said in the memo.

"With KKR’s investment and partnership, we will be able to accelerate our growth to reach more patients, deliver better patient outcomes, and expand our footprint across Vietnam," the memo added.

The board hoped to be able to accelerate our growth to reach more patients, deliver better patient outcomes, and expand our footprint across Vietnam with KKR's investment.

Founded in 2004, MSG has 13 hospitals in Vietnam, including eight ophthalmology hospitals and five general ones, according to its website.

Healthcare assets in Southeast Asia are attracting more interest as investors bet on the region's growth and the sector's ability to weather a challenging economic environment.

KKR declined to comment. Heliconia and MSG did not immediately respond to a request for comment.

The acquisition also marks KKR's first major private equity (PE) deal under its partner and Southeast Asia PE head Prashant Kumar since he moved to Singapore from India last year to lead KKR's PE business in the region.

KKR, which counts property group Vinhomes and education company EQuest among its investments in Vietnam, also invested in the Philippines' largest private hospital group Metro Pacific Health, according to its website.

KKR is active in Southeast Asia, where it invested $400 million into Malaysian subsea telecommunications cable services provider OMS Group in October and acquired a 20-percent stake in SingTel's regional data centre business for S$1.1 billion ($819.55 million) in September.