The US decision to exclude Turkey from an American-led fighter jet program goes against the "spirit of alliance," the Turkish government said Thursday, and called on its NATO ally to reverse the decision.
In a major break with a longtime ally, US President Donald Trump's administration on Wednesday said Turkey is being kicked out of the F-35 program because it is buying the Russian S-400 air defense system. Washington says the S-400 would compromise the F-35 program and aid Russian intelligence.
In a statement, Turkey's Foreign Ministry rejected that assertion.
"This unilateral step is incompatible with the spirit of alliance and is not based on any legitimate justification," the ministry said. "Not only is it unfair to keep Turkey out of a program of which it is a partner but the claim that the S-400 will weaken the F-35 is invalid."
The ministry said: "We call on the United States to come back from this mistake that will cause irreparable damage to our strategic ties."
On Thursday, Turkish President Recep Tayyip Erdogan's spokesman, Ibrahim Kalin, held a telephone conversation with White House national security adviser John Bolton, during which he expressed Turkey's unease over the U.S. decision, according to a statement from Erdogan's office.
During the call, Kalin said "one-sided impositions" would prevent the healthy progress of Turkish-US ties. Despite the tensions, the two also discussed a possible date for Trump to visit Turkey, according to the statement.
Turkey began taking delivery of components of the Russian system last week. A Russian cargo plane carrying more parts of the system landed at an air base near Ankara for a seventh day running on Thursday. Erdogan has said the system will be fully operational by April.
On Wednesday, Ellen Lord, the Pentagon's chief weapons buyer, told a news conference that the U.S. has suspended Turkey from the F-35 program and is beginning the process of its formal removal.
The US government is concerned that the S-400 could be used to gather data on the capabilities of the F-35, and that the information could end up in Russian hands.
Turkey has called for the establishment of a committee that would include NATO officials to study the risks.
Turkey refused to bow to US pressure to cancel the S-400 agreement with Russia, saying the deal is a matter of national sovereignty and that the agreement was a done deal.
Erdogan has said his government hopes to co-produce high-tech weaponry systems with Russia in the future, further defying the US and other NATO allies.
On Thursday, the head of Russia's state-controlled Rostech corporation said Moscow would be willing to sell Turkey its Su-35 fighter jets if Ankara "expresses interest."
The head of Turkey's defense industry body, Ismail Demir, said meanwhile that Turkey would look into possible "alternatives" and would also speed up efforts to develop Turkey's own fighter jet project, state-run Anadolu Agency reported.
He also said Turkey has fulfilled all of its obligations concerning the F-35 program and that Washington could lose $8 million per aircraft following Turkey's exclusion, Anadolu reported.
Turkey is both a producer and a customer of the F-35s. It makes more than 900 components for the stealth aircraft, which is sold internationally.
Lord, the Pentagon official, said Turkey stands to lose $9 billion in future earnings as an F-35 parts supplier.
She said the process of fully removing Turkey is underway and should be completed by March 31. She refused to say whether the decision could be reversed.