"This comes as the United States ends Ankara's participation in the advanced fighter jet program because of Turkey's plans to buy a Russian air defense system," Reuters reported.
The United States says the suspension of training at Locke Air Base came a few days after US Defense Secretary Patrick Shanahan told his Turkish counterpart that Turkish pilots already in the United States could stay there until the end of July. This would have given time for further training and also for Turkey to rethink its plans.
"The ministry is aware that the Turkish pilots at Locke Air Base will not fly," Lieutenant Colonel Mike Andrews, a spokesman for the Pentagon, told Reuters.
He added, "Unless there is a change in Turkish policy, we will continue to work closely with our Turkish ally on ending its participation in the F-35 fighter program."
Another US official told Reuters on condition of anonymity that a commander at the Locke base decided last week to stop training Turkish pilots and crews due to safety concerns.
The official said there were continuing aspects of the training of Turkish crews at the Eglin Air Base in Florida.
"If Turkey is excluded from the F-35 fighter jets program, this will be one of the biggest divisions in the relationship with the United States in recent history," experts said.
But the tensions in US-Turkish relations are already outstripping F-35 fighter jets. There is, for example, a conflict of strategy for Syria as well as sanctions on Iran and the detention of US consular personnel in Turkey.