State-owned Saudi Aramco plans to invest up to $1.6 billion for a nearly 20 percent stake in South Korean refiner Hyundai Oilbank, expanding its foothold in one of its biggest Asian buyers of crude oil.

Saudi Aramco is already the biggest shareholder in South Korea’s No.3 refiner, S-Oil Corp, with a 63.41 percent stake, and the latest deal should help Aramco boost crude oil sales to Hyundai Oilbank, the South’s smallest refiner by capacity.

Saudi Aramco’s chief executive told Reuters in November that it planned to expand its market share in Asia — including China, India, Malaysia and Indonesia — and Africa.