This citizen journalism image provided by Shaam News Network SNN, taken on Friday, Aug. 3, 2012, purports to show pillars of smoke as a result of shelling by Syrian government forces near al-Zafaran mosque in Homs, Syria. (AP Photo/Shaam News Network, SNN)
UNITED NATIONS (AP) — The four Western powers trying to rein in Iran's nuclear program accused Tehran on Thursday of shipping arms to Syria in violation of U.N. sanctions and ignoring demands to open key nuclear facilities to U.N. inspectors.
The United States, Britain, France and Germany expressed growing concern that Iran's goal is building a nuclear arsenal — not nuclear power plants for peaceful civilian use, as Tehran insists.
U.S. Ambassador Susan Rice told a Security Council meeting on the implementation of U.N. sanctions that members can't be complacent about Iran's "latest leaps forward in its prohibited nuclear activities."
"We must recognize that we are facing a situation that continues to worsen," she said.
A spokesman for Iran's mission to the U.N. did not immediately respond to an email seeking comment.
Rice and ambassadors from the other Western powers expressed serious concern at Iran's arms exports to President Bashar Assad's regime in violation of a U.N. ban against all weapons exports.
She reiterated the conclusion of the panel of experts monitoring implementation of sanctions that Syria is now the "central party to illicit Iranian arms transfers."
Britain's U.N. Ambassador Mark Lyall Grant said Iran's supply of weaponry to Syria is unacceptable and it must stop.
"It is in stark contrast to the will of the Syrian people and a reminder of Iran's hypocrisy in claiming to support freedom in the Arab world," he said.
France's U.N. Ambassador Gerard Araud accused Assad of massacring his own people and urged rigorous implementation of sanctions to keep Iran from providing his forces with the arms to accomplish his "sinister work."
Rice called on states in the region to "work together and redouble their efforts to deny, inspect and seize illicit Iranian shipments."
The 18-month Syrian conflict has escalated to a civil war which has killed more than 23,000 people, according to activists.
Germany's U.N. Ambassador Peter Wittig said reports indicate Iran is shipping arms to Syria "under a humanitarian pretext," which makes it crucial that all countries enforce the sanctions to keep pressure on Iran.
Russia and China, who have vetoed three Western-backed resolutions aimed at pressuring the Assad regime to end the violence and start talks with the opposition, made no mention of Iranian arms shipments to Syria in their speeches to the council but did address the nuclear issue.
On Iran's nuclear program, the Western powers expressed alarm at the latest report from the International Atomic Energy Agency. It said Iran has effectively shut down a probe of a site suspected of being used for work on nuclear weapons development while doubling the number of machines it could use to make the core of nuclear warheads at an underground bunker safe from airborne attack.
The nuclear concerns will be at the top of the agenda at a ministerial meeting of the four Western powers, Russia and China on Sept. 27 on the sidelines of the annual General Assembly gathering of world leaders that begins Tuesday.
"The Iranian regime is at a crossroads," Britain's Lyall Grant told the council. "It can continue to ignore the international community's concerns over its nuclear program, or it can negotiate a settlement that will help to realize the benefits of a civil nuclear program. It can support the oppressive regime in Syria in suppressing freedom, or it can play a constructive role in the region. It can be an exporter of terrorism or a responsible member of the international community."
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