The payment was made in December last year. President Donald Trump said last week in an interview with Fox News that Saudi Arabia "had already deposited $ 1 billion in the bank."
Bilateral negotiations are underway on exactly what expenses will be covered by the Saudis. That decision will lead to a final calculation of what the US believes the Saudis owe.
"Consistent with the president's direction to increase partner burden sharing, the Department of Defense has committed Saudi Arabia to share the cost of these deployments, which support regional security and deter hostility and aggression. The Saudi government has agreed to help. to subscribe to the cost of these activities and made the first contribution, "said the commander. Rebecca Rebarich, spokeswoman for the Pentagon. "Discussions are underway to formalize a mechanism for future contributions that outweigh the cost of these deployments."
The United States has sent thousands of additional troops and missile defense batteries to Saudi Arabia in response to what Pentagon officials said was a growing threat from Iran.
Saudi funds must cover the overall cost of deploying troops, as well as Patriot missile defense fighters and batteries to protect Saudi oil facilities from Iranian missile and drone attacks. The deployments began after what the Saudis said were Iranian attacks on oil facilities in September 2019.
The Saudi embassy in Washington did not respond to CNN's request for comment.
The US and several European countries blamed Iran for a missile attack that hit Saudi power facilities temporarily affecting the country's ability to produce oil.
The military buildup has occurred despite Trump repeatedly claiming that he wants to reduce US military engagement in the Middle East, a promise he cited in ordering US troop reductions in Syria, a movement that has received widespread bipartisan opposition in Congress, as many lawmakers see. this as an abandonment of the American partner in the fight against ISIS, the Kurdish-led Syrian democratic forces.
"In response to the heightened threats in the Middle East over the past eight months, the Department of Defense has sent US military forces to the region to enhance US defenses and increase Saudi Arabia's air and missile defense of critical military and civil infrastructure," said Rebarich.
Ongoing discussions with the Saudis aim to formalize a mechanism for future payments to offset the costs of deployments. But the Pentagon is insisting that future payments will not necessarily lead to the deployment of additional forces or additional military missions.
Separately, Saudi Arabia partially reimbursed the US for the cost of air refueling operations that the US military provided to Saudi warplanes, according to the US official.
The US stopped providing air refueling to Saudi jets participating in its Youth Yemeni rebel campaign in November 2018.
In December 2018, the US Army said it was seeking a $ 331 million refund from Saudi Arabia and the United Arab Emirates after finding that it had not adequately charged the Saudi-led coalition in Yemen for air refueling services.
The US official said the payments were made last year, with the full amount likely to be paid soon.
CNN's Ryan Browne contributed to this report.