Kahn also asked employees to "NOT comment about this publicly or on social media," CNN noted.
A spokesperson for the White House later confirmed the hire to CNN. The White House and Breitbart did not immediately respond to requests for comment from The Hill.
Once headed by Stephen Bannon, Breitbart became a highly popular source of right-wing political news during the 2016 campaign.
Bannon, who co-founded the news site more than a decade ago, served as White House chief strategist during most of President TrumpDonald TrumpMcAuliffe takes tougher stance on Democrats in Washington Democrats troll Trump over Virginia governor's race Tom Glavine, Ric Flair, Doug Flutie to join Trump for Herschel Walker event MORE's first year in office.
Bannon returned to Breitbart in August 2017 after leaving the White House. He later stepped down as chairman of Breitbart in January 2018.
CNN noted that another former Breitbart employee works in the Trump administration. Julia Hahn reportedly works as a special assistant to the president and director of surrogate and coalition communications.