Clandestine Afghan militias paid and supported by the CIA present an “obstacle” to U.S. peace-seeking efforts intended to end America’s longest war, according to a study released on Wednesday.

The U.S. military and the CIA assembled Afghan militias to fight jihadis after America’s invasion of Afghanistan in October 2001, soon after the September 11 attacks.

Nearly 18 years later, the CIA is still covertly paying and directing local militias in operations against the Taliban and other Islamic terrorists.

A new report from the Costs of War Project at Brown University’s Watson Institute questions whether the U.S. can fully integrate the militias into Afghan society post a peace agreement.

In the study, titled The “CIA’s Army”: A Threat to Human Rights and an Obstacle to Peace in Afghanistan, Brown University notes:

The CIA paramilitaries constitute a formidable set of actors in their own right. Given their highly paid and somewhat privileged status, they are unlikely to welcome a drastic reduction in pay that would accompany integration into the regular armed forces or demobilization. If cut loose by the CIA, they may be reborn as private armies or “security guards” in the service of powerful individuals, or operate autonomously to prey on civilians and commercial sources. Either possibility is in line with patterns of collective violence in modern Afghan history.

Acknowledging that “there is no public disclosure of the size of the CIA-supported units,” the study estimates that there are at least 6,000 CIA-backed militiamen.

The report notes that the secrecy behind its operations has rendered the paramilitary groups a menace to human rights, adding:

Throughout [the war], the militias reportedly have committed serious human rights abuses, including numerous extrajudicial killings of civilians. CIA sponsorship ensures that their operations are clouded in secrecy. There is virtually no public oversight of their activities or accountability for grave human rights

abuses.

The anti-Taliban militias present problems for reaching “a sustainable peace settlement”with the terrorist group, the report determines.

It explains:

Militias that operate outside the control of the central state and the chain of command of its armed forces will undermine the process of state formation and the prospects for a sustainable peace, as the experience of the massive international operation during the past 18 years demonstrates.

The study recommends that the U.S. end impunity for serious human rights violations and possible war crimes at the hands of the CIA-allied militias.

Doing so is “likely to strengthen rather than weaken the prospects for a peace settlement acceptable to the U.S. and the Afghan governments,” the report points.

After eight round of negotiations, the U.S. and the Taliban appear close to a peace pact.

Under the potential agreement, the Taliban has vowed to prevent Afghanistan from harboring international jihadis, engage in intra-Afghan talks, and agree to a ceasefire.

In return, U.S.-led foreign forces will leave Afghanistan.

The Trump administration is hoping for a peace agreement by September 1.

Currently, the primary point of contention appears to be divergent positions over the timeline for the withdrawal of U.S.-led international forces.

“While the United States has sought a window of close to two years, the Taliban have demanded a much shorter period,” the New York Times reports.

Zalmay Khalilzad, is expected to arrive in Qatar Wednesday for another round of discussions after briefing U.S. President Donald Trump over the weekend about the potential deal.

Trump has made no secret of his intentions to pull American forces out of Afghanistan in line with the desires of the American public.

However, the president has expressed a willingness to leave behind a residual intelligence and counterterrorism force to ensure the Taliban keeps its promises.

Taliban jihadis, however, have repeatedly rejected such proposals. The Brown University study suggests the CIA-allied militias could serve as assets for a residual U.S. force that will continue to combat terrorism.

The Taliban has intensified attacks amid the peace negotiations.

It appears the Taliban is not interested in sharing power with the government in Kabul.

The group, which is fighting to implement a sharia-compliant Islamic emirate, already considers itself the only legitimate government. Taliban jihadis control or contest about half of the country.

Although Afghanistan is home to the “highest regional concentration” of terrorist organizations in the world, per the Pentagon’s assessment, the American public has grown tired of the war.

The U.S. has devoted a tremendous amount of blood and treasure to the conflict — nearly $1 trillion, more than 2,290 American military deaths, and 20,507 injuries.

Several news reports have accused the CIA of being complicit in Afghanistan’s booming opium business. Opium is the primary ingredient in heroin.

Currently, the cultivation and trafficking of opium is the top source of funding for the Afghan Taliban. The Trump administration will not say if it is pushing the Afghan Taliban to cut its ties to opium and heroin as part of the ongoing peace talks.

U.S. officials have acknowledged that Afghan heroin has fueled the historic number of lethal overdoses in the United States in recent years. However, the Drug Enforcement Agency (DEA) stresses that Latin American traffickers remain the top source for the deadly drug.

Despite more than $9 billion devoted to counter narcotics efforts in Afghanistan, the country remains the world’s top producer of opium and heroin.