(CNN) -- President Donald Trump said Sunday that he anticipates shifting several positions in his administration, hinting that the departures could include Homeland Security Secretary Kirstjen Nielsen and White House chief of staff John Kelly.
"I have three or four or five positions that I'm thinking about," Trump told Fox News' Chris Wallace during an interview that aired on "Fox News Sunday." "Of that, maybe it's going to end up being two. Maybe. But I want to -- I need flexibility."
Trump has been mulling an administration shakeup in recent weeks, with Nielsen anticipated as possibly the next to go , multiple officials with knowledge of the matter have told CNN. The officials describe Trump as dissatisfied over Nielsen's handling of his key issues of immigration and border security. Trump has also floated possible replacements for Kelly, including Vice President Mike Pence's chief of staff, Nick Ayers.
In the interview, Trump praised Nielsen as intelligent, but stressed that she was not as "tough" as he wanted her to be.
"I like her a lot. I respect her a lot. She's very smart," Trump said of Nielsen. "I want her to get much tougher, and we'll see what happens there. But I want to be extremely tough."
When asked the chances that she would remain homeland security secretary, Trump said "there's a chance" she would, but that people who have left his White House have been successful.
"Well, there's a chance. But there's a chance everybody -- I mean, that's what happens in government. You leave, you make a name, you go," Trump said. "The people that have left have done very well. The people that have left have done very well, from my White House. I like her very much, I respect her very much. I'd like her to be much tougher on the border -- much tougher, period."
Trump also discussed Kelly's future, saying that while they "get along well" and Kelly is "doing an excellent job," there are some things that aren't his strength.
"There are certain things I love what he does, and there are certain things that I don't like that he does -- that aren't his strength," Trump said. "It's not that he doesn't do -- you know he works so hard. He's doing an excellent job in many ways. There are a couple of things where it's just not his strength. It's not his fault. It's not his strength."
Asked to elaborate on what he meant, Trump said, "But I haven't even thought about John in terms of this. But John, at some point, is going to want to move on. John will move on."
When questioned on whether Trump's promise last July that Kelly would be at the White House through 2020 was no longer definite, the President said, "Yeah, it could happen. Yeah, it could -- I mean, it could be. But let's see what happens."
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