Military vehicles and equipment, parts of the S-400 air defense systems, are unloaded from a Russian transport aircraft, at Murted military airport in Ankara, Turkey, Friday, July 12, 2019. The first shipment of a Russian missile defense system has arrived in Turkey, the Turkish Defense Ministry said Friday, moving the country closer to possible U.S. sanctions and a new standoff with Washington. The U.S. has strongly urged NATO member Turkey to pull back from the deal, warning the country that it will face economic sanctions. (Turkish Defence Ministry via AP, Pool) (Associated Press)

ISTANBUL — Turkey on Saturday continued receiving components of a Russian-made air defense system, despite Washington’s warnings that it will impose sanctions on the NATO-member country.

Turkey’s defense ministry tweeted the landing of a fourth Russian cargo plane in Murted Air Base, near the capital, Ankara. On Friday, the ministry announced the much-awaited delivery of S-400 components had begun.

The United States has repeatedly warned it will impose economic sanctions and kick Turkey out of the F-35 stealth fighter jet program if Ankara does not drop its S-400 purchase. Turkey has refused to bow to U.S. pressure, saying its defense purchase is a matter of national sovereignty.

The U.S. administration was publicly silent Friday on how it would respond to the delivery, with the Pentagon postponing a news conference.

Acting U.S. Secretary of Defense Mark Esper and Turkish Defense Minister Hulusi Akar spoke by phone. While the Pentagon declined to discuss the call, the Turkish ministry released a statement late Friday, saying Akar stressed that the purchase of S-400 defense systems “was not an option but rather a necessity” due to Turkey’s security concerns.

The statement said there was no change in Turkey’s “strategic orientation,” adding that a deterioration in relations would not serve the interests of Turkey, the U.S. or NATO.

The minister also emphasized Turkey’s commitment to the F-35 program and repeated a proposal for a joint working group to study how the S-400 system would interact with the fighter jets.

The U.S. is concerned the S-400 could be used to gather data on F-35 capabilities if Turkey has both.

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