Green Salt and the Iranian Laptop. The NYT's David Sanger and Elaine Sciolino report:

The Bush administration has agreed to turn over to international inspectors intelligence data it has collected that it says proves Iran worked on developing a nuclear weapon until a little more than four years ago, according to American and foreign diplomats.

The decision reverses the United States’ longstanding refusal to share the data, citing the need to protect intelligence sources.

The administration acted as the International Atomic Energy Agency is scheduled to issue a report as early as next week on Iran’s past nuclear activities. Administration officials hope that the nuclear inspectors can now confront Iran with what the Americans believe is the strongest evidence that the Iranians had a nuclear program.

The Bush administration’s refusal to turn over the data has been a source of friction with Mohammed ElBaradei, the director general of the agency, who has argued that Iran must be given a fair chance to examine some of the case that Washington has developed.

But it remains unclear how much of the data Dr. ElBaradei will be allowed to disclose to the Iranians. In particular, it is not clear if the information includes diagrams and designs that were secretly taken out of Iran on a laptop computer in 2004 and turned over to the Central Intelligence Agency. ...

According to American and foreign officials interviewed about the contents of the laptop, the information found there included descriptions of the so-called Green Salt Project. That project, which involved uranium processing, high explosives and a missile warhead design, demonstrated what the agency suspected were links between Iran’s military and its ostensibly peaceful nuclear program. If that evidence were substantiated, it would undercut Iran’s claims that its program is aimed solely at producing electrical power.

The documents on the laptop described two programs, termed L-101 and L-102 by the Iranians, describing designs and computer simulations that appeared to be related to weapons work. ...

The presentation included selections from more than a thousand pages of Iranian computer simulations and accounts of experiments that, according to the American officials, showed a longstanding effort to design what appeared to be a nuclear warhead or similar “re-entry vehicle.” ...