WASHINGTON: The United States has halted delivery of equipment related to the stealthy F-35 fighter aircraft to Turkey, markinB1g the first concrete US step to block delivery of the jet to the Nato ally in light of Ankara’s planned purchase of a Russian missile defence system.

US officials told their Turkish counterparts they will not receive further shipments of F-35 related equipment needed to prepare for the arrival of the stealthy jet, two sources familiar with the situation said on Monday.

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The Pentagon said that the equipment delivery had been stopped.

“Pending an unequivocal Turkish decision to forgo delivery of the S-400, deliveries and activities associated with the stand-up of Turkey’s F-35 operational capability have been suspended,” Air Force Lieutenant Colonel Mike Andrews, a Defence Department spokesman, said in a statement.

Turkish President Tayyip Erdogan has refused to back down from Ankara’s planned purchase of a Russian S-400 missile defence system that the United States has said would compromise the security of F-35 aircraft.

The disagreement over the F-35 is the latest of a series of diplomatic disputes between the United States and Turkey including Turkish demands that the United States extradite Islamic cleric Fethullah Gulen, differences over Middle East policy and the war in Syria, and sanctions on Iran.

The sources said the next shipment of training equipment, and all subsequent shipments of F-35 related material, had been cancelled. The aircraft is built by Lockheed Martin Corp.

A Pentagon official had said in March that the United States had a number of items it could withhold in order to send Turkey a signal that the United States was serious about Ankara dropping its ambition to own the S-400. Turkey has said it will take delivery of the S-400s in July.

The US decision on the F-35s was expected to complicate Turkish Foreign Minister Mevlut Cavusoglu’s visit to Washington this week for a Nato summit. On Sunday, Erdogan suffered one of his biggest electoral losses in decades in local elections.

“Certain Russian weapon systems are seen as inherently threatening to the United States regardless of who is operating them and for what purpose,” Andrew Hunter, a fellow at the Centre for Strategic and International Studies, said.

Published in Dawn, April 3rd, 2019