U.S.-backed opposition forces in Syria’s largest city are facing a ferocious Russian-led assault, raising fears that the rebels could be eliminated in a matter of weeks.

So how are the Pentagon and the intelligence community responding?

By catfighting among themselves.

Two Department of Defense officials told The Daily Beast that they are not eager to support the rebels in the city of Aleppo because they’re seen as being affiliated with al Qaeda in Syria, or Jabhat al Nusra. The CIA, which supports those rebel groups, rejects that claim, saying alliances of convenience in the face of a mounting Russian-led offensive have created marriages of battlefield necessity, not ideology.

“It is a strange thing that DoD hall chatter mimics Russian propaganda,” one U.S. official, who supports the intelligence community position, wryly noted to Pentagon claims that the opposition and Nusra are one in the same.

But even if the rebels were completely separated from Nusra, there would still be something of a strategic conflict with U.S. military goals. The rebels in Aleppo, these Pentagon officials note, are fighting the Bashar al-Assad regime; the American military effort, on the other hand, is primarily about defeating the self-proclaimed Islamic State.

“We have no role in Aleppo. The forces we are supporting… are fighting ISIS,” one defense official explained to The Daily Beast.

The intelligence community, which backed opposition forces in Aleppo, believes ISIS cannot be defeated as long as Assad is in power. The terror group, they say, thrives in unstable territories. And only local forces—like the ones backed by the CIA—can mitigate that threat.

“The status of the opposition is resilient in the face of horrendous attacks by the Syrian and Russian forces,” a U.S. intelligence official explained to The Daily Beast. “The defeat of Assad is a necessary precondition to ultimately defeat [ISIS]. As long as there is a failed leader in Damascus and a failed state in Syria, [ISIS] will have a place to operate from.

“You can’t deal with ISIS if you have a failed state,” the U.S. official observed.

The interagency squabble is a manifestation of growing tension about the U.S. approach to arming rebels, which is inconsistent across Syria.

The Defense Department currently is helping some rebels fighting ISIS in northern and eastern Syria, with more than 250 U.S. military advisers alongside forces marching toward the ISIS capital of Raqqa. This combination of fighters also is attacking the city of Manbij, which has served as a major thoroughfare for ISIS fighters, weapons, and supplies traveling from Turkey to Syria. Meanwhile, the CIA is backing some opposition forces in Aleppo, Syria’s biggest city and the site of a Russian- and Syrian-led air offensive over the past few weeks.

“The U.S. has two isolated programs that are not mutually supporting each other and are actually sometimes at odds with each other,” said Jennifer Cafarella, a Syria analyst at the Washington-based Institute for the Study of War.

Indeed, U.S. support for a particular group can change from one part of Syria to another. The Pentagon, for example, backs Kurdish forces associated with the YPG, the armed force of the Kurdish Democratic Union Party, in eastern Syria but not the YPG in northern Aleppo. Indeed, the YPG just north of Aleppo has attacked U.S.-backed forces with Russian help.

“We are not a country of agencies that butt up against each other. The White House needs to decide what its approach is toward Assad and the rebel groups. I think they do have a defined policy toward ISIS,” Daveed Gartenstein-Ross, a senior fellow at the Washington, D.C.-based Foundation for Defense of Democracies, told The Daily Beast.

The division within the Obama administration comes at a critical time for the war in Syria. Aleppo could descend into a months-long siege between opposition and Russian-backed government forces, endangering civilians and potentially creating a new refugee flow. That’s the better-case scenario. At worst for the opponents of the regime, Aleppo could fall under Assad control within weeks, potentially ensuring his survival. And yet the fall of Aleppo offers no guaranteed outcomes for the war. Indeed, it could encourage Assad’s opponents, like Turkey and Saudi Arabia, to increase their support for the opposition fighting on the front lines.

Regardless, Assad’s confidence was on display earlier this week when he addressed parliament and said he would rid Aleppo of its foreign-backed “terrorists,” going so far as to say Aleppo will eventually become Turkey’s “graveyard.”

“Our war against terrorism is continuing,” Assad said in a speech to parliament broadcast by state TV. “As we liberated [Palmyra] and before it many areas, we will liberate every inch of Syria from their hands. Our only option is victory, otherwise Syria will not continue,” Assad reportedly said.

Russia has said the strikes are targeting only terrorist outfits like Nusra, but such claims are increasingly hard to take seriously. Russian strikes have hit numerous hospitals and routes used by the more moderate opposition.

On Wednesday, at least 15 people were killed in two government air strikes in Aleppo, according to the Syrian Observatory for Human Rights, which monitors civilian deaths. One strike reportedly struck the Bayan hospital, killing at least 10. The observatory reported that barrel bombs dropped from government helicopters killed at least five others, including two children, in the Aleppo neighborhood of al-Marjeh.

And according to Institute for the Study of War, which maps attacks across Syria, the number of places that have come under Russian attack nationwide over the past five days has tripled—from roughly 10 to 30. Among the tactics Russia has deployed, according to ISW, is to launch a series of attacks along a main opposition supply route thoroughfare, Castello Road.

And yet there is no push with the Obama administration to give more arms to the opposition groups or increase support, and both defense and administration officials concede that crafting a strategy that appeals to all is difficult.

“It’s not clear there is a defined set of policies for helping the opposition where the benefits would outweigh the costs. And that is due to the problem with al Qaeda being such a strong force with the opposition. How do you strengthen the opposition without strengthening al Qaeda?” Gartenstein-Ross said.

To be sure, the U.S.-led coalition does not have the authority to go after the Syrian regime and its push to break the will of opposition. The U.S. military mission only authorizes strikes that target ISIS. Practically speaking, there are challenges, as well. The U.S. and Russia currently de-conflict to avoid disasters during their air campaign. That gives Russia something of a say in where U.S. strikes happen, and Assad’s backers are unlikely to make strikes against government forces targeting opposition forces easier.

Perhaps that’s why the U.S.-led coalition has not conducted any strikes around Aleppo in weeks, according to Pentagon statistics.

Whatever the outcome in Aleppo, critics argue the lack of a clear approach toward rebels weakens the U.S. ability to help resolve the five-year civil war.

“The most likely outcome in the near term is that these groups coalesce around hardline elements that are more effective,” Cafarella said