WASHINGTON — The Pentagon has approved a waiver that would allow Lockheed Martin to resume F-35 deliveries that were halted over the discovery of an alloy made using unapproved materials from China.

A Senate aide confirmed to Defense News that key lawmakers — including leaders from both parties on the Armed Services committees and members of other relevant committees — on Friday received a letter from the Pentagon saying undersecretary of defense for acquisition and sustainment William LaPlante had signed a waiver and that deliveries can resume.

The Pentagon and the F-35 Joint Program Office declined to comment for this story. Lockheed Martin said it had not been officially notified of the waiver and could not comment.

Politico first reported that Congress had been notified the waiver had been approved.

The Pentagon and Lockheed announced Sept. 7 that F-35 fighter jet deliveries were temporarily halted following the discovery that a subcontractor had made a magnet using a cobalt and samarium alloy that came from China. That magnet is part of a key engine component called a turbomachine, made by Honeywell. Lockheed said the supplier that provided the alloy was a fifth-tier supplier.

The Pentagon said the magnet does not transmit information or put the fighter at risk, adding that the fighters already delivered would not need their magnets replaced.

But due to concerns that the presence of Chinese-sourced materials may violate the Defense Federal Acquisition Regulation Supplement, the military decided to stop accepting new F-35s.

LaPlante said at a Sept. 9 briefing that the Defense Department’s investigation was moving quickly to confirm the alloy did not affect security, airworthiness and safety, and if so that a waiver would likely be issued to resume F-35 deliveries.

The F-35 Joint Program Office said last month the contractors involved are using a different source for the alloy for the turbomachine magnets.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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