This story was updated to clarify that contract negotiations are between the U.S. government and Raytheon, as the sale is through the Foreign Military Sales process.

WASHINGTON — Bahrain has signed a letter of offer and acceptance with the U.S. government to buy the Patriot air and missile defense system, triggering contract negotiations for the foreign military sale between the U.S. and Patriot-maker Raytheon, according to a company statement.

Bahrain is the newest and 17th customer of the Patriot worldwide, including the United States.

The kingdom is not disclosing the quantity of systems and missiles that might be on order, but the U.S. State Department cleared the possible foreign military sale of the Patriot in May for an estimated pric of $2.5 billion.

According to a Defense Security Cooperation Agency notification of the possible FMS sale, the deal would include 60 Patriot Advanced Capability-3 Missile Segment Enhancement missiles, 36 Patriot MIM-104E Guidance Enhanced Missiles with canisters, nine M903 launchers, two AN/MPQ-65 radar sets, control stations and association equipment.

Raytheon’s Patriot “will ensure the Kingdom of Bahrain is well-equipped to defend against ballistic missiles, cruise missiles, and manned and unmanned aircraft,” Ralph Acaba, company president of Raytheon’s Integrated Defense Systems business, said in the statement.

Recent new customers include Poland, Romania and Sweden. Other Middle Eastern customers include Saudi Arabia, Kuwait, the United Arab Emirates and Qatar.

Raytheon has seen a relative windfall in new Patriot customers over the past couple of years in deals totaling $18 billion, but all of those new customers are European and were responding to what they perceive as Russian aggression in the region.

Poland’s Patriot deal is expected to cost about $10.5 billion, according to State Department estimates.

Sweden is the newest customer after holding a competition to buy an air and missile defense system. The country will buy four fire units, 100 GEM-T missiles, 200 PAC-3 MSE missiles and other necessary equipment for roughly $3.2 billion.