US issues ultimatum to Turkey to backtrack on Russia’s S-400 system

Ellen Lord, Under Secretary of Defense for Acquisition and Sustainment, told reporters on Friday that agreements with Turkish firms sub-contracted for manufacturing the F-35 stealth warplane will be cancelled unless Ankara gives up on the S-400 system by July 31.

The deadline "will allow sufficient time for Turkish personnel associated with the F-35 program to be reassigned and depart the United States... to facilitate an orderly cessation of Turkish participation."

Two unnamed US officials told Reuters earlier on Friday that Washington would no longer accept any additional Turkish pilots to train on F-35 fighter jets.

Lord, however, said that even Turkish pilots currently training in the United States on the F-35 will be expelled too.

Currently, four Turkish pilots are receiving training on F-35 fighter jets at Luke Air Force Base in Arizona and two more are working as instructors at the base. An additional 20 Turkish aircraft maintainers are also participating in the program, according to the US military.

Lord justified the US ultimatum by the fact that Turkey, a NATO ally of the United States, already has its personnel in Russia waiting to be trained with the S-400.

US officials previously said they wanted Ankara to opt for the American Patriot system instead, saying that option would allow the F-35 program to continue.

Turkey, which plans to buy 100 US F-35s, said it told the US that Ankara would buy Patriots only if Washington's conditions of delivery were as positive as Moscow's.

"But unfortunately we haven't received a positive proposal from the American side on the subject of Patriots like the S-400s from Russia," Turkish President Recep Tayyip Erdogan said.

Acting US Defense Secretary Patrick Shanahan said he, in a letter, had informed his Turkish counterpart Hulusi Akar of Washington's new decision.

The US offer for the Patriots was "very competitive," Shanahan told reporters.

The S-400 is an advanced Russian missile system designed to detect, track, and destroy planes, drones, or missiles as far as over 400 kilometers away. It has previously been sold only to China and India.

Ankara is striving to boost its air defense, particularly after Washington decided in 2015 to withdraw its Patriot surface-to-air missile system from Turkish border with Syria, a move that weakened Turkey’s air defense.

Ankara has been critical of Washington for supporting Kurdish groups in Syria that he says are responsible for terror attacks inside Turkey, among other issues.