In what could be a major blow to U.S. plane maker Boeing (BA), Japan Airlines on Monday announced it has finally decided to purchase 31 A350 wide-body jets from Airbus, with a worth placed at $9.5 billion. Moreover, the purchase agreement between the two companies has options for a further 25 aircraft.

"This is a big win for Airbus," Chris de Lavigne, an aviation analyst, told BBC News.

"This was the final frontier for them and they have conquered it."

JAL airplanes at Osaka Itami Airport (Wikimedia)

The development has led John Leahy, Airbus sales chief, to state on Monday that the company was already well on its way to meeting its quota for the year 2013.

"We have an internal target of 1,200 (orders) but I think we could even do a little better than that," Mr Leahy told an industry conference. Between January to September 2013, Airbus has received 1,112 orders.

The purchase agreement with JAL and Airbus will become operational effective 2019. The new fleet with replace the airline's ageing fleet, primarily composed of Boeing 777s, over a six-year period.

"This was their market to lose, and they lost it," analyst Richard L. Aboulafia told New York Times.

The 31 A350s order by JAL would be enough to replace all of its current long-range 777s, essentially knocking off a later order for 777Xs.

"We will utilize the A350 XWB to maximum, which offers high level of operational efficiency and product competitiveness, while positively catering to new business opportunities after slots at airports in Tokyo are increased," Yoshiharu Ueki, president of Japan Airlines, said in a statement.

The A350-900 can comfortably seat more than 300 passengers on routes as long as 8,100 nautical miles. The A350-1000 is the largest member of the A350 XWB Family, seating 350 passengers on even longer missions up to 8,400 nm.