A top U.S. intelligence official says Iran would respond if attacked for its nuclear activities, but is unlikely to initiate or intentionally provoke a conflict.
That assessment comes from the director of the Defense Intelligence Agency, Lieutenant General Ronald Burgess. He told a Senate hearing Thursday that if Iran is attacked, it could respond by actions including shutting a vital shipping lane.
"Iran can close the Straits of Hormuz at least temporarily, and may launch missiles against United States forces and our allies in the region if it is attacked. Iran could also attempt to employ terrorist surrogates worldwide," said Burgess. "However, the agency assesses Iran is unlikely to initiate or intentionally provoke a conflict."
Burgess and Director of National Intelligence James Clapper both told the hearing it is believed that Israel has not made a decision to attack Iran.
A number of nations believe Iran is using its civilian nuclear program as a cover for developing nuclear weapons. Israeli leaders have warned repeatedly that Iran must be prevented from acquiring a nuclear bomb.
In Tokyo Thursday, Israel's Defense Minister Ehud Barak called for increased sanctions on Iran. Barak said that while current sanctions are affecting Iranian officials, more action is necessary.
"I think that the sanctions should be ratcheted up and made even more urgent," said Barak. "I think that for the first time we see certain signs of impact of these sanctions, but they might not suffice to compel the Iranian leadership to take decisions. So we feel that there is still a need for more effective and paralyzing sanctions on Iran."
The United States on Wednesday downplayed Iran's new claims of advances in its nuclear program, saying Tehran wants to distract from its growing diplomatic isolation.
Iran said it had installed a new generation of centrifuges to enrich uranium, and for the first time loaded domestically produced nuclear fuel into Tehran's research reactor.
U.S. State Department spokeswoman Victoria Nuland dismissed the announcements.
"We frankly don't see a lot new here,"said Nuland. "This is not big news. It seems to have been hyped. The Iranians have, for many months, been putting out calendars of accomplishments, and based on their own calendars, they are many, many months behind. This strikes us as calibrated mostly for a domestic audience."
Nuland says Iran must show its nuclear program is for civilian purposes.
"They still need to demonstrate to all of us, including taking advantage of the IAEA inspection team now, that this is a purely peaceful program as they claim," she said.
Iran hailed the advances as a step toward mastering the complete nuclear fuel cycle, despite U.N. and Western sanctions aimed at stopping the process. White House spokesman Jay Carney said Iran is making "defiant" statements because its leadership and economy are under "enormous pressure" from sanctions.
The European Union said Wednesday it received a formal Iranian reply to a letter sent almost four months ago offering Iran a resumption of nuclear talks with the five permanent U.N. Security Council members plus Germany - a group known as P5+1. The Iranians said they are ready for "dialogue" and "cooperation."
The parties last met in Istanbul a year ago but made no progress.
Some information for this report was provided by AFP, AP and Reuters.