Turkish Airlines will buy 51 planes from Airbus and Boeing Co worth about $4 billion at list prices under an agreement announced on Wednesday.
The deal for 36 European Airbus planes and 15 from its US rival Boeing coincides with a trip to Paris by Turkish Prime Minister Tayyip Erdogan, who discussed it with senior French officials on Tuesday.
Erdogan is trying to persuade France to back Ankara's bid to join the European Union and the state airline's decision to buy mostly Airbuses may be seen by some as political, though Airbus denied that.
"It's basically commercial, even if the politics go in the right direction," Airbus Chief Executive Noel Forgeard told reporters at the Farnborough air show near London.
Boeing said it was grateful for Turkish Airlines' plan to buy 15 of its single-aisle 737-800 planes worth about $900 million at list prices but was critical of suspected political influence.
"We were clearly disappointed by the up-front, obvious political effort," said Thomas Pickering, Boeing senior vice president for international relations. "We're concerned that EU expansion is becoming a sales tool for Airbus."
If Turkish turns its memorandum of understanding into firm orders, the new planes would boost its fleet by 60 percent in a long-awaited decision seen improving its prospects for privatisation.
Airbus said the 36 planes Turkish planned to buy were worth $3 billion before the discounts that are common in the industry.
"It's a very significant order ... It's worth over $2 billion," Forgeard told reporters, referring to the actual value.
Analysts had expected an announcement at the Farnborough air show, one of the industry's largest gatherings, yet the airline announced it in Turkey in a statement to the Istanbul Stock Exchange.
"We decided at our executive board meeting on Tuesday to buy five A330-200s, twelve A321-200s and nineteen A320-200 planes from Airbus and fifteen B737-800 jets from Boeing," it said.
BOEING VS AIRBUS: Boeing said the 15 737s would all add to its existing order book and that delivery would begin next year.
"Right now we're just finalising the contract details," said Boeing spokesman Michael Tull.
Airbus, owned by European Aeronautic Defence & Space Co (EADS) and Britain's BAE Systems Plc, also announced a smaller deal with Indian budget start-up Kingfisher for four of its A320 planes and options on eight more, worth as much as $770 million at list prices.
Airbus has said it will deliver at least as many planes this year as in 2003, when it bested Boeing for the first time in their three-decade rivalry, delivering 305 commercial jets.
The Toulouse, France-based plane-maker has notched up planned orders for planes worth $10.8 billion after the busy first three days of the Farnborough show.
Boeing, which insists it does not store up big announcements for air shows, has garnered orders and intended orders worth $3.9 billion.
At last year's Paris air show, Airbus and Boeing announced orders or planned orders worth $19.8 billion and $1.5 billion respectively.
RAPID EXPANSION: Turkish Airlines plans talks with financiers on how to fund its planned jet purchases but said it was confident it could raise the money. For the first time, it did not seek Turkish Treasury guarantees.
The airline, which is 98.17 percent owned by the state, said its 2003 profit of $200 million and full capacity on domestic flights had helped bolster its position.
Tapping a surge in domestic air travel triggered by an improving economy, Turkish said it expected annual turnover to rise to $2.5 billion in three years from $1.5 billion now.
It plans to expand its fleet to 89 planes in the same period.
A signing ceremony for the MOU was being held in Paris late on Wednesday.
Earlier this week, Finance Minister Kemal Unakitan said Turkey was considering a public offering of 15 to 20 percent of the carrier this year as part of its privatisation programme, which has so far faltered.
"This deal with Airbus and Boeing is good for (Turkish Airlines') privatisation because it brings fresh investment and is aimed at securing a larger market share," said Cem Marti, an analyst at Ata Investment.
"But I do not think it will give Turkey the upper hand in its bargaining to get into the EU. France will not change its position for $1.5 billion," he added.
EU leaders will decide in December, on the basis of a report from the European Commission, whether to open entry talks with Turkey, a relatively poor Muslim country of 70 million people.