As speculation widens that President Donald Trump may de-certify that Iran is complying with the so-called “nuclear deal” Tehran signed with the Obama administration, the State Dept. approved a deal to sell Saudi Arabia 360 THAAD missile defense interceptors.

The $15 billion deal would be the largest export of the sophisticated missile defense system if it goes through. Defending against missiles from archenemy Iran is the key reason behind Riyadh’s interest in purchasing THAAD.

“This sale furthers U.S. national security and foreign policy interests, and supports the long-term security of Saudi Arabia and the Gulf region in the face of Iranian and other regional threats,” the Defense Security Cooperation Agency, the arm of the Pentagon that oversees foreign arms sales, said in a statement Friday. “This potential sale will substantially increase Saudi Arabia’s capability to defend itself against the growing ballistic missile threat in the region.”

The Obama administration approved the sale of 600 Patriot missile interceptors to the kingdom in 2015, shortly after the deal was signed.

Iran’s elite Revolutionary Guards commander has threatened U.S. bases and forces in the region if Trump de-certifies Iranian compliance and if the Trump administration labels the Revolutionary Guards Corps a terrorist organization.

In all, the State Department approved the sale of 44 THAAD launchers, 360 interceptors, 16 command-and-control stations, seven radars and 43 trucks to move them around.

Congress was notified of the sale on Friday. If the Legislative Branch does not object within 30 days, the sale can proceed.

Why it’s on our radar: Information in this article helps satisfy Priority Intelligence Requirement 4: What are the latest indicators of a new war in the Middle East?  Each week in our Strategic Intelligence Summary, we gauge the likelihood and scope of conflict with Russia, China, North Korea, and in the Middle East, and track the latest developments in each region.  Subscribe here to receive our premium intelligence products prepared by Intelligence and special operations veterans.