WASHINGTON, Sept 12 (Reuters) - President Vladimir Putin and Russia are "isolated and alone" in asserting that Syrian rebels were likely responsible for the Aug. 21 chemical weapons attack on civilians near Damascus that prompted a U.S. threat of military action, the Pentagon said on Thursday.
Arguing against President Barack Obama's proposed U.S. military strike on Syria in an op-ed piece published in the New York Times on Thursday, Putin blamed the rebels for the attack.
Putin wrote that "there is every reason to believe it was used not by the Syrian army, but by opposition forces, to provoke intervention by their powerful foreign patrons, who would be siding with the fundamentalists."
Pentagon spokesman George Little, asked about Putin's piece, acknowledged the Russian president's efforts to seek a diplomatic solution to the crisis by getting Syria to hand over its chemical weapons to international control.
But Little reiterated the U.S. contention that Syrian President Bashar al-Assad's forces were responsible for the attack and he dismissed the possibility rebels could have done it. Little said more than 30 countries blame Syrian government forces.
"Let me respond with the following on the Putin op-ed: President Putin has invested his credibility in transferring Assad's chemical weapons to international control and ultimately destroying them. The world will note whether Russia can follow through on that commitment," Little told reporters at the Pentagon.
"Russia is isolated and alone in blaming the opposition. We've seen no credible reporting that the opposition has used chemical weapons in Syria," Little added.
"The evidence clearly points directly to the Assad regime's responsibility," he said.
The comments came as U.S. Secretary of State John Kerry flew to Geneva to hear Russia's plan to place Syria's chemical weapons under international control, an initiative that has transformed diplomacy over a 2-1/2-year-old civil war. (Reporting by Phil Stewart; Editing by Alistair Bell and Will Dunham)