? Panetta: U.S. policy toward Iran's nuke program is not about "containment," but about "prevention."

? Panetta said U.S. policy remains that Iran should not be allowed to develop a nuclear weapon.

? Tehran insists that its nuclear program is solely for civilian purposes.

U.S. Defense Secretary Leon Panetta on Friday reiterated that the U.S. policy toward Iran's nuclear program is not about "containment," but about "prevention."

Panetta made the remarks after meeting with visiting Canadian counterpart Peter MacKay, during which the two discussed issues of mutual concern, including Afghanistan and the Middle East, with particular emphasis on Iran's suspected program to develop a nuclear weapon.

The U.S. defense chief stressed that the U.S. policy remains that Iran should not be allowed to develop a nuclear weapon, while urging Tehran to respond to the international sanctions aimed at dissuading it from acquiring a nuclear bomb.

Tehran insists that its nuclear program is solely for civilian purposes, while the U.S.-led West and Israel suspect that it is aimed at creating a nuclear weapon that could be used to eliminate Israel.

Though Israel has been pushing for the use of force to destroy and delay the Iranian nuclear program, U.S. President Barack Obama, with an eye on winning re-election, believes there is still time for diplomacy and the economic sanctions to work to deter Tehran from crossing the red line.

Speaking at the United Nations on Thursday, Netanyahu said that a firm ultimatum should be issued to Iran to stop it from getting a nuclear weapon before next spring or early summer.

MacKay said that there have been a number of red lines placed already, but "Iran has edged closer and stepped over those red lines on a number of occasions now, particularly when it comes to cooperation around the subject of inspections."

On Syria, Panetta said there were some indications that the Syrian military had moved some of its chemical weapons recently, but the main bases holding the stockpile remain secure.

Panetta also discussed with MacKay the cooperation on Afghanistan between the two countries, thanking Canada for its support by deploying 500 troops to train Afghan security forces.

MacKay said there have been progress made in transferring security responsibility to Afghan forces, which will allow Afghanistan "to spread that security and spread that hope."

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