Updated at 1:27 p.m. ET.

The United States has shelved a program that was intended to train moderate Syrian rebel fighters.

As we've reported, the $500 million program, which sought to train 5,400 fighters, has failed. At last count, the U.S. said it had been able to train only about 60 fighters.

NPR's Tom Bowman reports that the new program will train so-called enablers at a site in Turkey. Those enablers will be opposition leaders who can collect intelligence about the location of Islamic State fighters and call in U.S. airstrikes in coordination with existing fighters.

During a briefing with reporters, Ben Rhodes, Obama's deputy national security adviser, said the administration was going to suspend its program of vetting and training individual fighters. Instead, the administration will now focus on vetting leaders and then providing them with equipment packages for their fighters.

Christine Wormuth, under secretary of defense for policy, said that for now, the Pentagon would not hand those leaders advanced weapons like anti-tank rockets and shoulder-launched surface-to-air missiles. In the future, she said, when they have built more confidence in the groups that calculation could change.

Defense Secretary Ashton B. Carter spoke about the changes after he met with is British counterpart in London earlier today.

"I wasn't satisfied with the early efforts in that regard, so we're looking at different ways to achieve basically the same kind of strategic objectives," Carter said.

Carter said they had "devised a number of different approaches to that going forward."

Tom says that U.S. is moving to arm Arab and Kurdish fighters, who the U.S. believes are ready to try to retake the northern city of Raqqa, an Islamic State stronghold.

Brett McGurk, the president's special envoy in the fight against the Islamic State, said that this is an evolving strategy because it involves the "most complex" and "most dynamic situation imaginable."

"Every part of the map is different. We need different tools at different points," he said. "I think we've learned over the past year the more we can be adaptive, the more we can look to seize opportunities as they arise, the more effective we can be. At the same time, the more we try to rigidly fit a square peg into a round hole and try to do things the way we might've envisioned them, the less effective we'll be."

Update at 12:50 p.m. ET. A Shift In Focus:

During a briefing with reporters, Christine Wormuth, under secretary of defense for policy, described the new approach as shifting the focus from vetting individual fighters to vetting their leaders.

Wormuth said that for now, the U.S. would be in contact with those rebel leaders and start providing them with equipment packages.

For now, Wormuth said, the U.S. won't be providing advanced weapons like anti-tank rockets and shoulder-launched surface-to-air missiles.

Update at 10:50 a.m. ET. Equipment To Select Group:

In a statement, the Department of Defense said that it was now moving to "provide equipment packages and weapons to a select group of vetted leaders and their units," who are poised to take territory currently controlled by the Islamic State.

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