ANKARA, May 28 (Xinhua) -- The U.S. attempt to block the delivery of F-35 fighter jets to Turkey has put the bilateral ties between the two NATO allies at risk, said an aide to Turkish President Recep Tayyip Erdogan.
In 2014, Turkish government placed an order for the first two F-35 jets for a projected fleet of 100 F-35A aircraft.
The F-35 jets are developed and built by U.S. defense contractor Lockheed Martin for the U.S., Britain, Australia, Italy, Norway, Turkey, the Netherlands, Denmark and Canada, in a project worth about 400 billion U.S. dollars, making it the world's most expensive arms program.
Turkish firms, including Aselsan, Kale Aviation, Roketsan, and Turkish Aerospace Industries, also take part in the production of the jets.
The ties between Ankara and Washington have soured in recent years over differences on Turkey's war inside Syria and Washington's refusal to extradite cleric Fethullah Gulen accused by Turkey of masterminding the failed coup in 2016.
Tensions further rose as Turkey signed a deal worth 2.5 billion dollars to purchase the Russian S-400 defense system, a move that raised concerns among Turkey's NATO partners.
Hence, although Turkey has been a co-partner of the F-35 project and already paid for part of its shares, a group of U.S. senators in April drafted a bill calling for excluding Ankara from the project, citing Turkey's defense deal with Russia and its imprisonment of the evangelical pastor, Andrew Brunson.
Brunson, a U.S. citizen who has lived in Turkey for over 20 years, was arrested in the aftermath of the botched military coup in Turkey in July 2016. He was charged with "espionage" and "terrorism," and faces up to 35 years in jail.
The U.S. administration led by President Donald Trump has called for the release of Brunson.
Last week, Turkish Foreign Ministry spokesman Hami Aksoy said Turkey would respond if the U.S. Congress passed the bill on blocking the delivery of F-35 jets to Turkey.
The Turkish government has showed its willingness to amend its ties with the U.S., but Washington seems to have no response, said Ilnur Cevik, a presidential aide.
"We want to overcome the problems with the United States. Close cooperation with the United States is essential," said Erdogan's ruling Justice and Development Party (AKP) in its announcement for holding elections on June 24.
"Erdogan's remarks meant 'Let's open a new chapter.' Did the United States understand this?" Cevik asked.
Murat Yetkin, editor-in-chief of Hurriyet Daily News, said that now almost all existing problems between Turkey and the U.S. have been tangled with each other and reflected on the F-35 issue, including the Syrian war, the Gulen case, and the Brunson case.
The F-35 controversy could cause a real collapse of the Turkey-U.S. ties, he warned.
A crucial meeting between U.S. Secretary of State Mike Pompeo and Turkish counterpart Mevlut Cavusoglu in Washington scheduled on June 4 will be an opportunity to put all the matters on the table.