Several in the White House were suspicious of Eric Ciarmella being a leaker before he was let go

Washington Examiner:

Steve Bannon, Trump's former White House chief strategist, says he worked to remove alleged Ukraine whistleblower Eric Ciaramella from the National Security Council in 2017.

Bannon, who was fired by Trump in August 2017, said he shared Trump’s daughter Ivanka's views about the whistleblower’s identity not being particularly relevant but added that he had worked to kick Ciaramella off the NSC during Trump’s first year in office. Bannon did not name Ciaramella, a career CIA analyst, but clearly referred to him.

“I agree with Ivanka. I don’t think the individual naming of the whistleblower is important, although there was a story in the Washington Times yesterday that tied me to the efforts to get the — at least the gentleman who was named — out of the National Security Council,” Bannon said during a Vice interview with Liz Landers last week.

It is possible Bannon was referring to a Washington Examiner article from last week that cited former National Security Council officials who said many on the NSC were suspicious of Ciaramella and believed he may have been responsible for leaking the contents of Trump’s discussions with the leaders of Mexico and Australia in 2017. The sources said former national security adviser H.R. McMaster was unhappy with efforts by Bannon and others to push out Obama holdovers such as Ciaramella, who was criticized by pro-Trump writers in 2017.

When Landers asked whether it was true he had tried to remove Ciaramella, Bannon responded: “The individual that was named? Absolutely true. When I was in the White House, there was a number of people on the National Security Council — the named individual eventually got let go, I believe because people were suspicious, and not me, but other people around him, were suspicious about his leaking, and that’s why he was let go.

"But I believe you don’t need to name the person, OK? But I do believe you need a thorough investigation of his intentions, relationships he’s had, etc.”

While the whistleblower's identity has not yet been confirmed, Ciaramella, 33, has been named widely and has issued no denial.
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If he was leaking he should have been removed from his position and turned over to the DOJ to consider prosecution.  The actions described look like those of a Deep State operative who opposed the President's policies.