The leak of highly classified U.S. intelligence documents describing recent satellite images of Israeli military preparations for a potential strike on Iran gives an indication of serious U.S. concern about Israel's plans. The New York Times reports.

In addition, U.S. officials are working to understand the extent of the improper disclosures.

Two documents were produced in recent days by the intelligence agency responsible for analyzing images and information collected by U.S. satellites.

The documents, which offer interpretations of the satellite images, offer insight into a possible Israeli strike on Iran in the coming days. Such a strike was expected in response to an Iranian attack earlier this month, which was in response to an Israeli attack.

One of the documents is titled “Israel: air force continues preparations for a strike on Iran” and describes a recent exercise that apparently practiced elements of such a strike. The second document details how Israel is changing the placement of its missiles and weapons in case of an Iranian response.

Officials are divided over the severity of the leak. The documents describe but do not show satellite imagery. If no additional documents are discovered, the damage will be limited. It would also again reveal the extent to which the U.S. is spying on one of its closest allies. 

Other officials say disclosing an ally's military plans is a serious problem.