Putin made a point of noting the Pentagon's recent admission that an effort to train more than 5,000 Syrian rebels had yielded only four or five fighters after about 50 others were captured, wounded or fled in their first encounter with extremist militants.
"It turns out that just 60 were properly trained, only four or five with weapons are fighting, while the rest of them simply took the American weapons and ran over to join ISIS," Putin, using an alternate acronym for the Islamic State group, said in the interview with U.S. networks CBS and PBS to be broadcast Sunday evening in the United States. The Kremlin released an excerpt of the interview earlier in the day.
Defending Russia's military buildup in Syria and support for President Bashar Assad, he described Assad's army as the only "legitimate" one in Syria.
The U.S. "provision of military support to illegal structures runs counter to the principles of modern international law and the United Nations charter," Putin said.
His statements show how far apart Russia and the U.S. remain on Syria.
Putin and Obama meet on Monday on the sidelines of the U.N. General Assembly, after both leaders address the annual gathering of world leaders.