In this Saturday, Feb. 3, 2007 file photo, an Iranian technician works at the Uranium Conversion Facility just outside the city of Isfahan 255 miles (410 kilometers) south of the capital Tehran, Iran. The sophisticated cyberweapon which targeted an Iranian nuclear plant is older than previously believed, an anti-virus firm said Tuesday Feb 26 2013, peeling back another layer of mystery on a series of attacks attributed by The New York Times to U.S. and Israeli intelligence.(AP Photo/Vahid Salemi)
Iran's Supreme National Security Council Secretary and chief nuclear negotiator Saeed Jalili gestures during a meeting on Iran's nuclear program, in Almaty, Wednesday. Seeking even a small step forward in a yearslong dispute, negotiators from Iran and six world powers mulled options for preserving Tehran's nuclear program while still trying to keep it from becoming an atomic arsenal. (AP Photo/Shamil Zhumatov, Pool)
WASHINGTON: Secretary of State John Kerry said in an interview that the U.S. is nearing a final “crunch time” on Syria — in which it will either make progress toward a cease-fire or begin moving toward “Plan B” and new military moves.