(CNN) - Former President Bill Clinton said Wednesday that Russian President Vladimir Putin can be trusted, but cautioned the United States will "just have to see what happens" over efforts to disarm Syria of its chemical weapons.
"You work for the best and prepare for the worst in this business. But I think it would be a terrible mistake not to take advantage of the opportunity," he told CNN's Piers Morgan at the Clinton Global Initiative annual meeting in New York. "And, you know, look, Mr. Putin is very smart."
Watch more of the interview Wednesday on CNN's "Piers Morgan Live," starting at 9 p.m. ET.
Clinton said he knows the Russian president well, and they have a "brutally blunt" relationship. He said Putin had never reneged on a personal agreement with him.
"He kept his word in all the deals we made," Clinton said.
While Putin became president shortly after Clinton left the White House in 2001, he had served as Russia's prime minister during the latter end of Clinton's second term.
Shortly after Russia announced that it would work with the United States to try and forge a diplomatic solution on disarming Syria of its chemical stockpiles, many congressional lawmakers raised questions over whether Moscow could be trusted, given its strategic alliance with the regime of Bashar al-Assad.
President Barack Obama has even expressed doubt, but argues diplomacy would be preferable to military action, though he's not against using force if an agreement doesn't materialize.
During his speech Tuesday at the United Nations General Assembly, Obama challenged the international community to enforce its ban on chemical weapons by agreeing to put pressure on Syria - even militarily - if the regime fails to relinquish those weapons to international control.
He called for a "strong" resolution from the Security Council, of which Russia is a member, to "verify that the Assad regime is keeping its commitments."
U.N. inspectors returned to Syria on Wednesday to look into at least a half-dozen claims of chemical weapons use. The United Nations, as well as the United States, confirmed sarin gas was used in an attack on suburb of Damascus on August 21. U.S. officials blame al-Assad's forces and have said more than 1,400 were killed. Syria denies it used chemical arms.
– CNN's Tom Cohen contributed to this report.
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