The language used in a letter sent from Washington to Ankara regarding Turkey’s removal from the F-35 fighter jet program does not suit the spirit of alliance, Turkish Defense Minister Hulusi Akar said on Wednesday.

Axar.az reports citing Reuters.

US acting Secretary of Defense Patrick Shanahan’s letter to his counterpart, seen by Reuters, had outlined how Turkey would be pulled out of the F-35 fighter jet program unless Ankara changes course from its plans to purchase a Russian missile defense system.

Akar, cited by the defense ministry in a statement, also said Turkey is preparing a response to the letter and that it would be sent to the US in the coming days. He added that he would hold a phone call with Shanahan on Thursday.