LONDON--Low-cost airline Ryanair Holdings PLC (RYA.DB) said Tuesday it has signed an agreement with the Boeing Company BA, +2.42% to buy 175 new Next Generation 737-800 airplanes in a deal, when finalized, that will be worth nearly $15.6 billion at current list prices.

MAIN FACTS:

-Approximately 75 of these new aircraft will replace some of Ryanair's existing fleet of 305 Boeing 737s, but the remainder will drive new growth of Ryanair's fleet.

-Airplanes will allow Ryanair to grow its low-cost airline service by about 5% per annum over the next several years, taking Ryanair's traffic to over 100 million passengers by March 2019.

-Ryanair continues to evaluate the benefits of Boeing's 737 MAX aircraft which enters service in 2017.

-Consideration payable will be in cash.

-Ryanair shares in London at 0915 GMT up 2 cents, or 0.38%, at 582 cents valuing the airline at 8.42 billion Euros.

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