(CNN) -- The United States and the United Arab Emirates have signed a deal for a missile-defense system in the Persian Gulf country, the Pentagon said Friday.
The $3.48 billion agreement was signed December 25, according to press secretary George Little. It was not clear why the deal was announced Friday.
The vital Strait of Hormuz separates the UAE and Iran. The Obama administration said Iran has been "saber-rattling" over its threat to block the strait.
The pact will deliver two anti-missile batteries, 96 missiles, radars, training and logistics to the UAE, the Pentagon said.
"Acquisition of this critical defense system will bolster the UAE's air and missile-defense capability and enhance the already robust ballistic missile-defense cooperation between the United States and the UAE," the Pentagon said.
The two countries "enjoy a strong bilateral defense relationship, driven by common interests in a secure and stable Gulf region," Little said in a statement.
Raytheon Company said it will provide two radars and services through 2018 to the country. "This $582.5 million contract for the radars is part of the first sale of THAAD missile systems to an international customer," it said in a statement.
CNN Pentagon correspondent Barbara Starr contributed to this report.