The policy shift, first reported by The Wall Street Journal, allows the CIA and the U.S. Joint Special Operations Command to fire on targets based solely on the targets' intelligence "signatures" -- patterns of behavior detected through signals intercepts, human sources and aerial surveillance that indicate the presence of an important operative or a plot against U.S. interests -- the officials told the Journal and The Washington Post.
White House and CIA officials declined to comment.
The White House decision, agreed to this month, stops short of giving the CIA and JSOC the Pakistan-style blanket powers that had been sought, the officials said.
CIA drones flying over Pakistan's tribal belt are allowed to strike groups of armed militants traveling by truck toward the war in Afghanistan, for example, even when there is no indication of the presence of al-Qaida operatives or a high-value terrorist, the Post said.
One U.S. defense official described the approved authorization to the Journal as "signature lite."
The targets are suspected members of al-Qaida in the Arabian Peninsula, a militant Islamist group named for al-Qaida and claiming allegiance to it.
AQAP, formed in January 2009, is considered the most active of al-Qaida's branches, or "franchises."
Advocates of expanding the scope of U.S. drone strikes in Yemen say fresh U.S. intelligence indicates AQAP has grown stronger since one of its prominent leaders, U.S.-born Yemeni Muslim cleric Anwar al-Awlaki was killed Sept. 30, 2011, in a drone strike in Yemen, the Journal said.
U.S. counterterrorism officials say Awlaki was the main force behind AQAP's decision to transform itself from a regional threat into al-Qaida's most active branch.
Washington applied considerable pressure on Yemen to step up the program, a high-ranking Yemeni intelligence official told the Journal.
Yemen insisted on tough limitations, out of fear a stepped-up Yemeni drone program could resemble what one Yemeni official called an "out-of-control" drone program in Pakistan, the Journal said.
"Every Yemeni is armed," this official said. "So how can they differentiate between suspected militants and armed Yemenis?"