AQAP is known as the most active and dangerous branch of the terrorist organization and is led by Nasir al-Wuhayshi, second-in-command for al-Qaida worldwide.
The video, first reported by CNN, shows about 100 members of al-Qaida gathered outside around al-Wuhayshi, who seems unconcerned about an American drone strike and tells members of the need to "eliminate" the U.S.
"We must eliminate the cross. ...The bearer of the cross is America!" he says in the video.
U.S. officials have said the video is authentic and are analyzing it frame by frame for any potential signs of new plots. The did not comment on whether they knew about the meeting or why drone strikes were not deployed if they were aware.
The Pentagon has sent multiple drone strikes to take out AQAP leaders, but this group appeared to not be concerned. One of the members of the group is Ibrahim al-Asiri, a bomb maker who can create bombs that cannot be detected on planes -- like the one used in the failed underwear bombing attack on Christmas Day 2009 in Detroit.
"Sooner or later, if they continue to get better, stronger and more organized," Kimmitt said, "they will be a direct threat to the United States."