A transpartisan coalition of groups calling itself “​​a diverse network of transparency and advocacy organizations” sent a letter to Senate leaders on Wednesday urging them “to take steps to ensure that all U.S. aid to Ukraine is subject to independent oversight,” primarily by confirming permanent inspectors general at the Departments of Defense and State.

Since Russia launched its invasion in late February, Congress has approved more than $50 billion in humanitarian and military assistance to Ukraine with, as the New York Times noted, “the leaders of both parties rais[ing] few questions about how much money was being spent or what it would be used for.”

Many are also worried that American weapons sent to Ukraine may end up in the wrong hands. Indeed, referring to so-called “Switchblade” drones the United States is supplying Ukraine, a senior Pentagon official said last month that the Defense Department doesn’t know where they are or whether they’re being used. “They’re not telling us every round of ammunition they’re firing [at] who and at when. We may never know exactly to what degree they’ve using the Switchblades,” the official said.

The dozen groups that signed the letter to Congress — which include Public Citizen, Taxpayers for Common Sense, and the Quincy Institute — say that “the sheer magnitude and speed at which the federal government is sending aid calls for robust oversight in terms of both spending and monitoring its use.”

The letter comes just days after 22 House Republicans sent a letter to President Biden expressing “grave concern about the lack of oversight and accountability for the money and weapons recently approved by Congress for Ukraine,” adding that “this money has not been tracked in any meaningful way nor have the American people or elected officials been informed of its effectiveness or use.”

The groups said Sen. Rand Paul’s proposal to place such monitoring in the already existing Special Inspector General of Afghanistan Reconstruction — given its expertise and oversight experience — is “reasonable.” But they worry such efforts will delay needed aid to Ukraine. They’re also concerned that Sen. John Kennedy’s proposal to create a new “SIGAR” for Ukraine has deficiencies in transparency and oversight.

“Therefore,” the groups say, “we encourage you—first and foremost—to confirm Rob Storch to be the inspector general at the Department of Defense, and to call on the administration to nominate an inspector general for the Department of State.”