(CNN) President Donald Trump has told aides he wants fewer people working for him in the White House and only loyalists installed in key administration positions, several people familiar with the matter say.

Trump's allies have provided him lists -- not always solicited -- of people they've identified as disloyal and of names they say would work better toward advancing his agenda. The lists have been generated over the past three years, but some are being dusted off in the post-impeachment purge.

It's not clear how seriously Trump takes the recommendations. But after hearing for three years from acquaintances and confidants about various people deemed disloyal, his efforts seem to have newfound urgency.

Trump told people recently he wants to take action on removing some people who he's been "warned about," according to one person who's spoken to him.

Some of the conservative activists who have been working on the effort to compose the lists include Ginni Thomas, the wife of Supreme Court Justice Clarence Thomas, and Senate staffer Barbara Ledeen.