The United Nations has delivered more than $2.9 billion in cash to Afghanistan since the Taliban seized control, resulting in the flow of U.S. funds to the extremist group, according to a recent government report.

The U.N. deposits the cash into a private Afghan bank and disburses funds to the agency’s aid organizations and nonprofit humanitarian groups. But the money does not stop there, the report found. Some winds up at the central bank of Afghanistan, which is under the control of the Taliban. The group took over the country after the withdrawal of U.S. forces in August 2021.

The report, from the Special Inspector General for Afghanistan Reconstruction, provides the first detailed account of how U.S. cash falls under the control of the Taliban and adds to a growing body of evidence that contributions to the U.N. are not always reaching Afghans in need. It did not specify how much U.S. funding has been channeled to the central bank.

“Most of the money that’s going in cash through the U.N. is ultimately coming from U.S. taxpayers,” John Sopko, the inspector general, said in an interview. “It’s going to a terrorist group. The Taliban are a bunch of terrorists.”

U.N. officials do not deny that the cash delivered to Afghanistan makes its way to the central bank. But they say there is no avoiding it since the Taliban control the country.

In a briefing to the U.N. Security Council on March 6, Roza Otunbayeva, the U.N.’s special representative for Afghanistan, did not mention the Afghan central bank. The cash shipments, she said, have helped stabilize the economy and deliver desperately needed medical care and food to Afghans. The shipments have “injected liquidity to the local economy that has in large part allowed the private sector to continue to function and averted a fiscal crisis,” Otunbayeva told council members.

In a letter provided in response to the inspector general’s report, the State Department said the U.N. was responsible for managing the cash transfer program.

“We remain committed to providing critical, life-saving humanitarian assistance to the Afghan people. We will continue to monitor assistance programs and seek to mitigate the risk that U.S. assistance could indirectly benefit the Taliban or could be diverted to unintended recipients,” the letter said.

Lawmakers say the U.S. must do more to prevent the flow of money to the group.

“This is unacceptable,” said Rep. Michael McCaul, the Texas Republican who chairs the House Committee on Foreign Affairs, in a statement. “The U.S. government must work harder to prevent the Taliban from benefiting from humanitarian aid.”

A spokesperson for the Afghan central bank did not return requests for comment.

Since the Taliban takeover, Afghanistan has suffered numerous humanitarian crises, with half its 40 million people in need of food, water and other basic necessities. Earthquakes last year killed more than 1,200 people and left thousands displaced. Women’s rights have been severely curtailed.

The U.S. remains the largest donor of aid to Afghanistan, providing a total of about $2.6 billion since the collapse of the previous Afghan government. But fears over money ending up in the wrong hands have complicated aid delivery. For instance, U.S. officials have blocked the central bank from receiving money from a trust fund holding Afghan funds that could be used to benefit the country.

“We could not be more clear on this: The United States does not provide funding to the Taliban,” said Matthew Miller, a State Department spokesperson, at a briefing last year.

The inspector general report calls that assertion into question. The State Department and the U.S. Agency for International Development have continued to provide money to the U.N. to assist ongoing humanitarian efforts. The U.N., in turn, has said it must send cash to Afghanistan because of the lack of an infrastructure to wire money.

After getting the money from the Federal Reserve Bank of New York, the U.N. flies shrink-wrapped $100 bills to the Kabul International Airport. The money arrives on a regular basis, as much as $40 million at a time, according to posts from the Afghan central bank on X, formerly known as Twitter.

Once aid organizations receive the U.S. dollars, they must convert the money into afghanis, the country’s currency, to pay for workers and other expenses. They often use private money exchanges, which use the dollars to purchase afghanis from the central bank, known as the Da Afghanistan Bank.

Senior leaders of the Taliban control the central bank, which has no systems in place to prevent terrorism financing or money laundering, according to the inspector general’s report, which cites an analysis paid for by USAID. Officials at the development agency declined to release the study, describing it as a “confidential internal document.”

When money leaves the central bank, there’s yet another concern. Humanitarian organizations are sometimes forced to pay cash directly to the Taliban. Local Taliban leaders have demanded that the U.N. and aid groups hire its members and their relatives or prioritize treatment of widows and wounded militants, according to the inspector general.

“Aid diversion does happen, and when it does, humanitarian work has to halt and solutions need to be found,” said one U.N. official who was not authorized to make public comment. “There are cases where the Taliban seek to take control of distribution according to their priorities, or other cases where aid work is stopped altogether. In other areas we see very positive support and openness.”

The risk of the diversion of foreign aid in wartorn countries has long bedeviled the U.S. and other countries. The only way to stop it would be to halt the flow of money — which humanitarian groups have said could lead to disastrous consequences such as starvation or the collapse of local economies.

In many ways, the U.S. is responsible for the problems it now faces. The distribution of funds to help the vulnerable was a repeated issue during two decades of war in Afghanistan and Iraq. American officials flew more than $12 billion in cash — that’s 363 tons — to Iraq in the early days of the war, according to congressional investigators, making it nearly impossible to determine the final beneficiaries.

But the U.S. and its international allies failed to ever fully implement systems to improve transparency, such as wire transfers or electronic payments, in Afghanistan, despite repeated pleas for such technology by watchdog organizations.

Sopko, the inspector general, said the U.S., the U.N. and multilateral agencies could install better controls over the delivery of cash in Afghanistan, but he acknowledged the inherent difficulty of the task.

“If nobody’s paying attention, then you’re going to have waste, fraud and abuse, big time,” he said.