Veterans Affairs Secretary Bob McDonald said more than 1,400 officials and workers "have been terminated" from the agency since he's been secretary but stressed that accountability is "more than just firing people."

Another 100 more, he said, are under investigation by the FBI for potential criminal behavior for cooking the books to make the backlog in patients appointments appear better than it was.

"For all of our critics, accountability in an organization is much more than just firing people," McDonald said at a Politico Playbook breakfast Thursday morning. "What we've got to do is make sure there's a sustainable system in place so that people are rewarded when they do well, people are held accountable when they don't do well – we're providing feedback."

No one in the VA Health Administration, he stressed, is getting a performance bonus for 2014 and no one's performance was rated as outstanding.

"How can you be rated outstanding if your secretary has to resign?" he said, referring to VA Secretary Eric Shinseki's resignation in late May of last year.

Since the VA appointment backlog first broke nearly two years ago, both he and Shinseki have worked to get average wait times for appointments down to 125 days and have required the agency's workers to work mandatory overtime to process the backlog of veterans' health claims.

He said he's trying to ease the strain on VA employees by allowing many of them to telecommute "so the two hours they used to commute, they can now do claims instead."

In addition, he said he has worked to raise VA doctors' salaries to make them more competitive with the private sector.

There is still far more work to do he said, pointing out that the biggest problem he faces is that he's not moving fast enough to fix the problem and that he takes full responsibility if there is "one veteran without a roof over their head" or who isn't getting adequate care.

He likened the problem of the VA healthcare backlog and homelessness plaguing the community to the metaphor of thousands of dying starfish that have been washed onto a beach and the tide recedes.

"It's such a large system and such a large need," he said. "It's how do you get [to] every single person?"

"I might not be able to clean up the whole beach, but it matters to every starfish [you throw back] in the water. But I want to clean up the whole beach," he said.

The House recently passed a bill, the VA Accountability Act of 2015, which makes it much easier for McDonald to fire poor-performing employees.

It still must pass the Senate and be signed by President Obama, who has threatened a veto.

Obama said the bill, which is sponsored by Rep. Jeff Miller, a Florida Republican who chairs the House Veterans Affairs Committee, is "counterproductive" and would create a "disparity in the treatment of one group of career civil servants."

The president also argued that it would have a negative impact on the VA's ability to retain and recruit qualified workers.