UN Nuke Inspectors Leave For Key Talks In Tehran [VIDEO]

A senior U.N. nuclear expert says his team is leaving for Tehran with hopes that Iranian officials will agree to talk about suspicions that the Islamic Republic has worked -- or is working -- on a clandestine atomic arms program.

Herman Nackaerts of the International Atomic Energy Agency is heading a group of experts focusing on the allegations, which Iran continues to deny.

Nackaerts told reporters Sunday before boarding a flight to Tehran "the highest priority remains of course the possible military dimensions of Iran's nuclear program."

The trip is the second one in less than a month as the IAEA attempts to dent nearly four years of Iranian refusal to cooperate with its probe. IAEA experts came back from their last visit in late January with no concrete results.

US, Britain urge Israel to let sanctions work

The U.S. and Britain are urging Israel not to attack Iran's nuclear program.

Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, and British Foreign Minister William Hague say an Israeli attack on Iran would have grave consequences for the entire region, and sanctions should be given more time to work.

National security adviser Tom Donilon is in Israel to meet with top officials.

The U.S. and Israel both believe Iran is trying to build a nuclear bomb. The U.S. says international sanctions must be given

more time to stop Iran. Israel says time is running out and all

options, including military action, must be considered.

Tehran says its nuclear program is for peaceful purposes.

(Copyright 2012 by The Associated Press.  All Rights Reserved.)