The YouTube clip, entitled "Official Statement," takes the form of a series of video statements based on those commonly released by Syrian armed groups, with a commander reading a proclamation as fighters brandish guns and flags behind him.
In the first "statement," set at the start of the uprising, the fighters vow to overthrow President Bashar al-Assad in an amateurish video punctuated by miscues and laughter.
But as the siege deepens, subsequent statements show fewer and fewer fighters, speaking in front of shelled out buildings and asking for help from the international community and other rebels.
At one point, the battalion leader gives fighters outside the siege "48 hours... to move from your chairs, your pulpits and from behind your laptops."
But months later, nothing has changed, except that three of the battalion members have died and two others have fled.
The seven-minute video was released Friday by a group called A Patch of Light from Homs and has been viewed over 7,000 times on video-sharing site YouTube.
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An activist in Homs told AFP via the Internet that the video was made in the besieged districts of the city, once known as the "capital of the revolution."
It was not clear whether the men in the video are fighters or civilians in real life.
The government and rebels are currently fine-tuning a deal that will see the last pockets of opposition fighters withdraw from rebel-held areas in the city, dealing a painful symbolic blow to the uprising against Assad.
The last scene of "Official Statement" shows only the battalion leader and a lone fighter with his head wrapped in a white bandage, too weak to lift his assault rifle from his lap.
"We announce that we will not announce anything else after today, because we have no fuel left, so we can't upload any more announcements," the battalion leader says.
"All we have left is our resistance. And all you have left are your promises and your betrayal. History is our witness."