Current and former intelligence officials who asked not to be identified said the plan aims to upset Iran's uranium enrichment program as well as alleged assistance to insurgents in Iraq.

By being designated as non-lethal, the CIA and Bush administration avoid having to tip their hand, said Richard Clarke, a former White House counter-terrorism official.

"There are some channels where the United States government may want to do things without its hand showing, and legally, therefore, the administration would, if it's doing that, need an intelligence finding and would need to tell the Congress," Clarke told ABC.

Bruce Riedel, a recently retired CIA senior official who dealt with Iran, said he had no knowledge of the plan but said economic pressure would likely be the most effective tool available to the CIA with regard to ferreting out secret accounts used to fund the nuclear program.