WASHINGTON (Reuters) - Iran could be within one to three years from developing a nuclear weapon and time is running out for diplomacy to defuse the problem, the top U.S. military officer has said.
The assessment from Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, matches that of some independent analysts but appears to go further than recent official statements from the U.S. government.
"Most of us believe that it's one to three years, depending on assumptions about where they are right now. But they are moving closer, clearly, and they continue to do that," Mullen said on ABC's television program "This Week" on May 24.
Since coming to power in January, President Barack Obama has made some diplomatic overtures to Iran that have so far been rebuffed. He said last week he would not pursue this policy indefinitely and would like to see some progress on the nuclear issue by the end of this year. Iran says its nuclear program is peaceful and intended to produce electricity.
Iran last week successfully tested a missile that analysts said could hit Israel and U.S. bases in the Gulf, a major source of crude oil for the United States.
Mullen said a military strike against Iranian nuclear facilities could have grave consequences -- but so would a nuclear-armed Iran.
"The unintended consequences of a strike against Iran right now would be incredibly serious," he said. In Congressional testimony last week, he used the word "calamitous" to describe the same scenario.
Israel has said it could not accept a nuclear-armed Iran while the United States has also refused to rule out military action. Iranian President Mahmud Ahmadinejad has repeatedly stated the Jewish state should not exist.
"That's why this engagement in dialogue is so important. I think we should do that with all options on the table as we approach them," Mullen said.
"And so that leaves a pretty narrow space in which to achieve a successful dialogue and a successful outcome, which from my perspective means they don't end up with nuclear weapons," he added.
His words went further than recent statements by Defense Secretary Robert Gates who said of Iran on March 1: "They're not close to a stockpile, they're not close to a weapon at this point and so there is some time."
Director of National Intelligence Dennis Blair told the U.S. Congress in February: "We continue to assess Iran probably has imported at least some weapons-usable fissile material but still judge it has not obtained enough for a nuclear weapon."
The United States and other Western powers are concerned that Iran could combine elements of its uranium-enrichment and missile programs to create a nuclear weapon, although Tehran denies it intends to do this.
A recent report by the joint U.S.-Russian think-tank EastWest Institute said Iran could develop a basic nuclear device in one to three years and a missile-borne nuclear warhead five years after that.
Mullen did not respond when asked if it was possible to take out Iran's nuclear program militarily at an acceptable cost.
"I won't speculate on what we can and can't do. Again, I put that in the category of my very strong preference...to not be put in a position where we -- where someone -- where Iran is struck," he said.