While normally shying away from official statements concerning the 11-month Syrian uprising, Israel’s Ambassador to the U.N. Ron Prosor on Monday urged the international community to stop the bloodshed in Syria, telling the General Assembly that Syrian President Bashar al-Assad has “no moral authority to govern.”

Prosor told the assembly that the graphic pictures emerging from Syria and the reports of bloodshed cannot be ignored. The U.N. estimates that more than 5,000 people have been killed in the 11-month-long uprising that aims to topple Assad’s regime and seeks reform.

“These pictures of helplessness in the face of death serve as a moral call to every person and every nation in the world,” Prosor said. “Nowhere is that call more clear than here at the United Nations, which was founded primarily to safeguard the principles of human rights, dignity and life.”

Prosor went on to say that Assad is “systematically murdering civilians…and his tanks are trampling on the rights of peaceful protestors. His forces are raping and torturing men, women and children.

“Bashar-al Assad may have been trained as an eye doctor, but in practice he only tries to blind the international community to the crimes of his regime,” Prosor told the assembly. “The international community can no longer afford to see the situation in Syria with anything less than 20/20 vision.”

The Israeli envoy implored the international community “to stop standing on the sidelines watching murder after murder.”

Assad and his regime have no moral authority to govern, Prosor said. “It is high time for this organization to start doing something meaningful to stop him from killing his own people. The children of Syria - from Homs to Hama - cry out to us. Their fate is in our hands.”

Meanwhile, the U.S. and its allies are closely monitoring Syria’s stockpiles of chemical arms and portable anti-aircraft missiles, a State Department official said, amid concerns that the country’s unconventional weapons could fall into the hands of terrorist or militant groups while the uprising continues.

“Syria is a country of significant proliferation concern, so we monitor its chemical weapons activities very closely,” the State Department official said, speaking on condition of anonymity to discuss intelligence-related matters. “We believe Syria’s chemical weapons stockpile remains under Syrian government control, and we will continue to work closely with like-minded countries to impede proliferation [of] Syria’s chemical weapons program.”

The official added that the U.S. is in discussion with its allies on ways to ensure that Syria’s stockpile of portable anti-aircraft missiles, called Man-Portable Air Defense Systems, or MANPADS, aren’t stolen or diverted. “We are consulting with allies and partners as we plan for a variety of contingencies,” the official said.

Republicans in Congress, meanwhile, have been critical of U.S. efforts to secure Libya’s chemical and unconventional arsenals, saying the Obama administration should have responded more quickly during that crisis and now faces the task of trying to account for thousands of missing portable anti-aircraft missiles.

“We got off to a slow start with Libya,” Rep. Edward Royce, chairman of the House Foreign Affairs subcommittee on terrorism, nonproliferation and trade, said in a recent interview.

Libya halted its weapons of mass destruction programs in 2003 as part of an agreement reached to improve relations with the West. Moammar Gadhafi’s remaining stocks of mustard gas were awaiting destruction when rebels drove him from power last year.

Gadhafi, however, maintained a large conventional arsenal, including an estimated 20,000 portable anti-aircraft missiles, believed to be the largest stockpile outside of a MANPADS-producing country.

Syria is believed to have nerve agents as well as mustard gas, Scud missiles capable of delivering these lethal chemicals and a variety of advanced conventional arms coveted by insurgent and terrorist groups, including some late-model MANPADS and anti-tank rockets. U.S. intelligence officials in the past have said Syria has conducted biological weapons-related research but have stopped short of saying the country had taken the next step and built bioweapons.

The task of securing Syrian President Bashar Assad’s arsenals is complicated by the fact that the U.S. can’t be certain it knows how many weapons Syria has and where they are stored. “There’s a lot to worry about and oftentimes very little information to assess the situation,” said Matthew Schroeder, a small arms researcher with the Federation of American Scientists.

According to independent military experts, Syria had more than 4,000 portable anti-aircraft missiles in the late 2000s. But Syria is a major customer of arms suppliers, including Russia, and could have purchased many more since then.

Israel and its allies long have suspected Syria of seeking at least the capacity to build atomic weapons, and the U.N. nuclear watchdog agency has pressed for information about Syria’s nuclear research program. But a 2007 airstrike, attributed to Israel in the international press, on a suspected plutonium-producing reactor under construction in northern Syria may have derailed Syria’s nuclear ambitions.

Israeli officials this month said their main worry is that Syria’s Lebanese ally, the militant Iranian-backed Shiite Muslim group Hezbollah, could acquire Syria’s Soviet-design S-125 surface-to-air missile systems, which could hinder operations by the Israel Air Force. But Israeli officials also said they were concerned Hezbollah could get its hands on chemical weapons and missiles capable of striking deep inside Israel.

Syria’s chemical arms are believed to be secure for now because they are stored at weapons depots in rural areas, officials and experts say, away from the urban centers where most fighting is now taking place.

“So far at least I don’t think we’ve seen any examples among troops that are guarding these sites or any activities to suggest the chain of command is weakening,” said Leonard Spector, a former senior nonproliferation official with the National Nuclear Security Administration. “I think what people are worried about is that the situation could become increasingly chaotic and the chain of command breaks down.”

But if Syria’s control of its arsenal collapses, he said, the consequences could be worse than in Libya. “It’s a hundred times more serious in Syria,” he said.

Andrew Shapiro, the assistant secretary of state for political-military affairs, said this month that the U.S. has helped recover 5,000 of Libya’s portable anti-aircraft missiles, or about a quarter of the number the Gadhafi government is thought to have amassed.

Shapiro said many of the weapons that have not been accounted for were likely used in training, had broken down or were fired by rebels while fighting the regime. A substantial number probably remain in the hands of militias who defeated Libyan government forces and were often the first to “liberate” weapons sites, he said.

“Yet clearly we cannot rule out that some weapons may have leaked out of Libya,” Shapiro said in a talk to the Stimson Center, a Washington nonproliferation group.

The U.S. plans to spend $40 million helping Libya secure and recover its stockpiles of portable anti-aircraft weapons, Shapiro said. The U.S. also will conduct an inventory of all Libyan weapons storage areas and has two mobile teams assigned to respond to the discovery of new portable missile caches, he added.

Royce and other Republican lawmakers said that if Syria’s arsenals are threatened, the Obama administration should move faster than it did in Libya to secure unconventional weapons.