Johnny DeStefano, a counsellor to the President, and Shahira Knight, the White House legislative Affairs Director, separately disclosed on Tuesday they would leave for new opportunities, reports The New York Times.
"Beyond grateful to @realDonaldTrump and @FLOTUS for the opportunity to serve in the best job I've ever had," DeStefano wrote on Twitter, calling the job "the honour of a lifetime".
Trump tweeted in response: "Johnny, we will miss you - you did a great job!"
Knight said in a statement that it was "a great honour" to serve Trump. "I will always be grateful for the experience I have gained, and proud of the accomplishments I have helped achieve alongside a very talented White House team."
Trump said she had done "a wonderful job" for him. "She was outstanding for us and for our country and will be a tremendous success in the private sector."
DeStefano has been a key member of Trump's circle since he took office. He was in charge of the Offices of Presidential Personnel, Intergovernmental Affairs, Political Affairs and Public Liaison.
Knight took over as legislative director only 10 months ago, making her the President's official envoy to Congress.
As of Tuesday, before the latest announcements, turnover among the most senior positions had reached 68 per cent, far more than any White House in the last four decades.
( With inputs from IANS )