BREAKING: Obama admits US underestimated IS threat

President Barack Obama admitted Sunday that the United States had underestimated the opportunity that a collapsing Syria would provide for militants to regroup and stage a sudden comeback.

Speaking to CBS News, the president said that former Al-Qaeda fighters driven from Iraq by US and local forces had been able to gather in Syria to form the newly dangerous Islamic State group.

"I think our head of the intelligence community, Jim Clapper, has acknowledged that they underestimated what had been taking place in Syria," he said, referring to his director of national intelligence.

Asked whether Washington has also overestimated the ability or will of Iraq's US-trained military to fight the militants on its own, Obama said: "That's true. That's absolutely true."