Ryanair shareholders have approved the deal to buy up to 200 Boeing 737 MAX airplanes.
Ryanair first announced its intention to purchase the aircraft in September.
Following the shareholder approval, one hundred firm orders will now be placed for the aircraft and Ryanair will have the option to purchase a further 100. When the deal is finalised it will be valued at over $22 billion.
Chief executive Michael O'Leary said that the new aircraft will allow Ryanair to lower its costs and fares.
He added, "This order will expand our fleet to approximately 530 aircraft by 2024 and create another 10,000 jobs for pilots, cabin crew and engineers in Europe, while allowing us to grow our traffic to over 150 million per annum."