A US Senate committee has passed a defence bill that would see Turkey barred from purchasing Lockheed Martin F-35 Joint Strike fighter jets as tensions continue over its detention of US citizen Andrew Brunson.
Brunson, a Christian pastor, has been charged with terrorism and spying by Turkish authorities, and could be jailed for up to 35 years later this month. He has been in pre-trial detention since 2016.
The amendment to the National Defence Authorisation Act (NDAA) from Democrat Senator Jeanne Shaheen and Republican Senator Thom Tillis yesterday, was also motivated by Turkey's agreement with Russia in December to buy S-400 surface-to-air missile batteries, which according to Shaheen, is sanctionable under US law.
"There is tremendous hesitancy [about] transferring sensitive F-35 planes and technology to a nation who has purchased a Russian air defence system designed to shoot these very planes down," Senator Shaheen said.
Earlier today, Turkish Foreign Ministry spokesperson Hami Aksoy told reporters that the measure was "against the spirit of our alliance with the US", but that Ankara would respond if the amendment was passed.
"This is not a programme managed solely by the US. It is a multinational programme and we expect everybody to fulfil their obligations," Aksoy said, noting that Turkey has fulfilled its obligations regarding the F-35 programme.
Relations between Ankara and Washington have been strained over a host of issues in recent months, including US backing of Kurdish militias in Syria, deemed terrorist organisations by Turkey, and a number of legal cases against Turkish and US nationals being held in the two countries.
Earlier this month, Turkish President Recep Tayyip Erdogan, who is facing upcoming elections in June, said that he would have preferred to work alongside the US in Syria, but that his offer was rebuffed.
"Let's fight together in Raqqa, was what I said to President Trump personally. And stop supporting PYD [Kurdish Democratic Union Party] and YPG [Kurdish People's Protection Units]. Don't walk hand in hand with these terrorists or that'll be a mistake. But unfortunately, the US preferred moving with them and set aside Turkey," he told CNN.
Tensions have also heightened over the case of Fethullah Gulen, a Muslim cleric living in Pennsylvania whom Ankara has blamed for the failed military coup in 2016. Turkey has been seeking Gulen's extradition for over a year, calls which have been ignored by the US.
Turkish authorities allege that Brunson was a citizen of Gulen's network, considered a terrorist organisation by the government. The US has said that Brunson has been wrongfully imprisoned and has called for him to be released.
Last year, President Erdogan suggested that Turkey would free Brunson in exchange for Gulen, calls which were dismissed by the Trump Administration.