Kuala Lumpur-based Malaysia Airlines has exercised an option to purchase 10 additional Next-Generation 737-800s from Boeing, in an order valued at more than $800m (£493.3m) at current list prices.
The airline still has purchase rights for an additional 10 Next-Generation 737-800s remaining from their initial 2008 contract.
According to Boeing, the 737-800, which can seat up to 189 passengers, is 771km lighter and can fly 583km farther while carrying 12 more passengers than the competing model.
Malaysia Airlines operates a mixed fleet of short and long-haul aircraft, including 747 passenger and freighter, 777, 737-800s and Classic 737 aircraft, with which it flies almost 45,000 passengers daily to more than 100 destinations worldwide.