President Trump gives an update on First Lady Melania and advisor Hope Hicks during an exclusive interview with Dr. Marc Siegel on Fox News.
Two administration officials said that Hicks' departure had been planned and was not related to the controversy surrounding riots at the Capitol last week.
Hicks worked as senior counselor to the president after returning to the administration in March of last year. Before joining then-candidate Trump's 2016 presidential campaign, Hicks worked for his corporation.
She went on to serve as White House director of strategic communications before departing and becoming Fox News' chief communications officer.
News of Hicks' departure comes on the same day that the House of Representatives voted to impeach Trump for a second time, accusing him of inciting Wednesday's riots at the Capitol.
In the aftermath of that event, several administration officials resigned, including Education Secretary Betsy DeVos and Transportation Secretary Elaine Chao.
Fox News' Kristin Fisher conributed to this report.