The Bush administration has prepared a list of terrorist leaders the Central Intelligence Agency is authorized to kill, if capture is impractical and civilian casualties can be minimized, senior military and intelligence officials said.

The previously undisclosed C.I.A. list includes key Qaeda leaders like Osama bin Laden and his chief deputy, Ayman al-Zawahiri, as well as other principal figures from Al Qaeda and affiliated terrorist groups, the officials said. The names of about two dozen terrorist leaders have recently been on the lethal-force list, officials said. ''It's the worst of the worst,'' an official said.

President Bush has provided written legal authority to the C.I.A. to hunt down and kill the terrorists without seeking further approval each time the agency is about to stage an operation. Some officials said the terrorist list was known as the ''high-value target list.'' A spokesman for the White House declined to discuss the list or issues involving the use of lethal force against terrorists. A spokesman for the C.I.A. also declined to comment on the list.

Despite the authority given to the agency, Mr. Bush has not waived the executive order banning assassinations, officials said. The presidential authority to kill terrorists defines operatives of Al Qaeda as enemy combatants and thus legitimate targets for lethal force.