President Barack Obama, in a sweeping address to the United Nations general assembly on Tuesday, challenged the international body to take “strong” action against Syria's use of chemical weapons or risk becoming irrelevant.

In his first broad foreign policy speech since an Aug. 21 chemical attack carried out by the regime of Bashar Assad, Obama forcefully urged the United Nations Security Council to pass a resolution to ensure Damascus gives up its chemical weapons arsenal.

“The Syrian government took a first step by giving an accounting of its stockpiles,” he said. “Now, there must be a strong Security Council resolution to verify that the Assad regime is keeping its commitments. And there must be consequences if they fail to do so.

“If we cannot agree even on this, then it will show that the United Nations is incapable of enforcing the most basic of international laws,” Obama added. “On the other hand, if we succeed, it will send a powerful message that the use of chemical weapons has no place in the 21st century and that this body means what it says.”

Obama earlier this month threatened a military strike against Syria for using chemical weapons, by delayed that measure after finding weak support on Capitol Hill.

Secretary of State John Kerry negotiated a deal with his Russian counterparts that would see Syria disarm by 2014 under the watch of international observers.

Obama, though, has vowed to keep military action on the table to ensure Syria follows through on the deal.

In a clear jab at Russian President Vladimir Putin, Obama also made the case that America will continue to be a global leader.

“The danger for the world is that the United States … may disengage creating a vacuum of leadership that no other nation is ready to fill,” he said. “I believe that would be a mistake.”

“I believe America must remain engaged for our own security. I believe the world is better for it,” he continued. “Some may disagree, but I believe that America is exceptional – in part because we have shown a willingness, through the sacrifice of blood and treasure, to stand up not only for our own narrow self-interest, but of the interests of all.”

In a recent New York Times op-ed, Putin criticized the idea of “American exceptionalism,” arguing that all countries should view each other as equals.