President-elect Donald Trump has been critical of the intelligence community as it outlines its findings on Russia’s interference in the U.S. election -- and one former top intelligence official said Mr. Trump’s comments are having “significant effects” on morale at the agencies.

“The president-elect has done two things: he’s questioned the capabilities of the intelligence community publicly,” said Michael Morell, the former acting CIA director and a former adviser to Democrat Hillary Clinton’s campaign. “But the other thing he’s done which is actually more damaging I think is he’s questioned the intelligence community’s integrity by implying that their assessment was politically motivated.”

Mr. Trump and his team have expressed skepticism in the intelligence community’s conclusions about Russia since the CIA first announced last month that it had “high confidence” Russia intervened in the election on Mr. Trump’s behalf. A statement from the Trump transition team at the time said of the intelligence agencies: “These are the same people who said Saddam Hussein has weapons of mass destruction.” Since then, Mr. Trump and his team have suggested the report itself is politically motivated.

There will be “significant effects if the disparagement continues,” Morell continued.

Mr. Trump’s criticism is a “gut punch to people who go to work every day, nonpartisan, apolitical, trying to call it like they see it,” he said. “...It has undermined morale in the intelligence community and at CIA and that’s a big issue.”

Morell said the most telling thing about the intelligence agencies’ Russia report is the label of “high confidence” -- which he said is not handed out lightly.

“We don’t attach that label to any judgment,” he said. “To have high confidence you have to have multiple sources, you have to have direct evidence, more than a circumstantial case.”

James Woolsey, a former CIA director and former national security adviser to Mr. Trump’s campaign, said he expects Mr. Trump to evolve -- and perhaps back off Twitter -- as he takes office later this month.

“The 140-character rule of tweets that basically governed a lot of the behavior during the campaign is looked at differently as one moves into governance,” he said, noting that Mr. Trump is different in a small-group setting than he is on Twitter or at his campaign rallies. “...You’re going to see growth and evolution on a number of these issues over the course of the next several weeks, and I would advise people not to hold him to a detailed support for everything he’s said on Twitter during the campaign.”