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A newly discovered video posted on a pro-Syrian regime website shows rebel commanders talking about their own “red line” after the government allegedly launched a chemical attack against civilians there last month.

The tape was reviewed by multiple analysts who said at the very least the rebels appeared to be issuing an ultimatum – if there was no military response to the attack by the West, they threatened to pursue their own chemical weapons.

Last year, President Obama described any use of chemical weapons in Syria as a “red line” that would warrant a response.

The four and a half minute video posted two days after the Aug. 21 Damascus attack features rebel commanders speaking while a black and white Islamist flag flies in the background.

Fox News Middle East specialist Walid Phares, who reviewed the tape, said, "The narrative is jihadi and the red line they're talking about is about the use of weapons they have not used before -- and what comes to my mind would be chemical or biological."

A separate analysis identified one of the men as a deputy to General Salim Idris, the leader of the Free Syrian Army, the same group some members of Congress describe as the moderate opposition in Syria.

Yigal Carmon, the president of the Middle East Media Research Institute, who also reviewed the tape, said,"The message is if the West doesn't act, we (the rebels) too will have no red lines, and will use chemical weapons."

While there is no evidence the opposition has chemical weapons, the possibility of their use has been discussed according to Phares.

"A year ago on some of the jihadi chat rooms, including in Syria, there has been talks about using all of the weapons needed and it's ideologically permissible for them to use those weapons," he said.

At the same time, and apparently compounding the situation, the flow of foreign fighters into Syria has grown significantly according to Thomas Joscelyn of the Foundation for Defense of Democracies.

"This a dire situation where we have the Assad regime which is despicable in one hand and Al Qaeda and its allies on the other," Joscelyn said. He estimated there were 10,000 Islamist fighters in Syria and many are battle hardened and effective.

"A big part of the problem here is the extremist groups, including Al Qaeda, basically have the best fighters, the best trainers, the best leaders for this type of jihad,” he said. “So even groups that are not extremist in nature tend to defer to them in the fighting because they're the most efficient.

"What we're seeing inside Syria right now is very much a replay of what happened in Iraq. In Iraq, we underestimated Al Qaeda's designs on the country and what they were trying to do."

The true composition of the rebels is a question the House and Senate intelligence committees, led by Republican Mike Rogers, and Democrat Dianne Feinstein respectively, continue to wrestle with according to a former senior staff member.

"This is what the American people pay millions and millions and billions of dollars for -- to be able to ask of the intelligence community the very hard questions of who people are and what their motives are," said Michael Allen, former staff director of the House Intelligence committee.

"It's an imperfect business, but I think we're getting there and we can have some confidence that there are elements of the rebels that we can support."