An Emirati soldier watches over Yemeni territory while riding a Chinook helicopter en route to a Saudi-led coalition air base in the Kingdom in 2015.Abdelhadi al-Ramahi / Reuters

President Donald Trump, who repeatedly complains that the United States is paying too much for the defense of its allies, has praised Saudi Arabia for ostensibly taking on Iran in the Yemen war. It turns out, however, that U.S. taxpayers have been footing the bill for a major part of the Saudi-led campaign, possibly to the tune of tens of millions of dollars.

The revelation—detailed in a Defense Department letter obtained by The Atlantic—is likely to raise further ire among senators who have grown ever-more critical of Saudi conduct in the war, which has resulted in a growing number of civilian casualties, and U.S. support for it.

Since the start of the Saudi-led intervention, in March 2015, and up until last month, the United States provided mid-air refueling for Saudi-led coalition aircraft that then flew missions related to the Yemen campaign. Getting heavy U.S. tankers into the air and carrying out this job is enormously expensive. The recipient country is required by law to pay the costs, but that isn’t what happened here. In a mea culpa of sorts, the Pentagon’s November 27 letter states that while the Defense Department “believed” Saudi Arabia and the United Arab Emirates “had been charged for the fuel and refueling services, they in fact had not been charged adequately.” How inadequately, the Pentagon will not yet say; it is “currently calculating the correct charges,” the letter states.

On Thursday, the Pentagon confirmed the letter’s contents to The Atlantic. “Although DoD has received some reimbursement for inflight refueling assistance provided to the Saudi-led coalition (SLC), U.S. Central Command recently reviewed its records and found errors in accounting where DoD failed to charge the SLC adequately for fuel and refueling services,” Commander Rebecca Rebarich, a Pentagon spokeswoman, told The Atlantic.

The Pentagon’s letter says that it reached these conclusions after Senator Jack Reed, the top Democrat on the Senate Armed Services Committee, made a specific request for information.

Reed, along with seven other Democratic senators, raised the question of reimbursements in a letter to Defense Secretary Jim Mattis in March. The Pentagon’s response admitting “errors in accounting” arrived the day before a key Senate procedural vote on withdrawing U.S. support for the war effort.

“It is clear that the Department has not lived up to its obligation to keep Congress appropriately informed or its responsibility to secure timely reimbursement,” Reed told The Atlantic. “U.S.-provided aerial refueling assistance was provided to the Saudi-led coalition for more than 3.5 years, activities that likely cost tens of millions of dollars. We must ensure that U.S. taxpayers are fully reimbursed for that support.”

When asked by The Atlantic how much reimbursement DoD had received from the Saudi-led coalition, Rebarich said that “CENTCOM is still working through the calculation.” The Saudi and UAE embassies in Washington had not responded to The Atlantic’s requests for comment about any reimbursements at the time of publication.

Jeffrey Prescott, who served as senior director for Iran, Iraq, Syria, and the Gulf States on the National Security Council in Barack Obama’s administration and is now a strategic consultant to the Penn Biden Center, told The Atlantic: “This is a striking revelation. President Trump has been exceedingly transactional, even seeming to threaten to cast aside NATO if our closest allies didn’t increase their contributions. That is why it is jarring to see that the Trump administration—save for congressional and public pressure—would continue to refuel Saudi and Emirati aircraft without adequate, if any, reimbursement.”

The U.S. refueling of Saudi-led coalition aircraft has long been a source of confusion, because the military has offered differing statements about how much fuel it has provided to its coalition partners. Hill staffers have spent years trying to pin down details of the arrangements, which are carried out via “acquisition and cross-servicing agreements,” or ACSAs, essentially bilateral treaties between the United States and a partner country that allow for the provision of military and logistical support. In the November 27 letter, the Pentagon admitted that the U.S. military refueled Saudi Arabia’s aircraft for at least the first year of the war without any ACSA with the Kingdom.

In the letter, written by Principal Deputy General Counsel William S. Castle, the Pentagon suggests that Saudi Arabia was treated as a “third party” for the first year of the war, receiving fuel via the UAE, who had a separate ACSA agreement dated to 2006. Such third-party arrangements are now explicitly prohibited under the latest defense spending bill, signed into law in mid-August.

It’s unclear if Castle’s explanation was arrived at after the discovery of the accounting error. After the first year of the Yemen war, the U.S. drafted a provisional ACSA with the Saudis, but the Pentagon says that Congress was never notified because the Kingdom, even today, hasn’t “fulfilled all of its internal procedures necessary for an Agreement to enter into force.” In short, throughout the entire duration of U.S. refueling, the Pentagon admits there was never an official servicing agreement in force with Saudi Arabia.  

Evidence exists that the military was, at certain levels, tracking fuel sales. Records provided by the Defense Logistics Agency this March indicated that since the start of fiscal year 2015 (October 2014), more than 7.5 million gallons of aerial refueling had been provided to the UAE, and more than 1 million gallons to the Saudis. Those figures were for all aerial refueling, not necessarily only related to operations in Yemen. Separate DLA data showed that at least some payments had been made by the UAE, though it was unclear to what degree they were tied to operations in Yemen. The Atlantic has asked the DLA whether either set of figures were affected by accounting errors. On Friday, the DLA said it was looking into those questions.

Next year, the Government Accountability Office is expected to release a report on the use of ACSAs, which may shed more light both on the way they were used in the Yemen war and countries where they’ve been employed with little scrutiny. The Senate, meanwhile, is set to vote on whether to cut off support for the coalition next week.

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