White House Deputy National Security Adviser Mira Ricardel has left her post, following a high-profile row with US First Lady Melania Trump.
A White House spokeswoman said Mrs Ricardel "departs the White House to transition to a new role within the administration". She did not elaborate.
Mrs Trump this week said that Mrs Ricardel "no longer deserves the honour of serving in this White House".
The two reportedly feuded during a tour of Africa in October.
The removal of Mrs Ricardel comes amid reports in US media that President Donald Trump is considering a shake-up in the White House West Wing.
Trump may be preparing to remove White House Chief of Staff John Kelly or Department of Homeland Security Secretary Kirstjen Nielsen, the reports say.
The announcement of the transfer of Mrs Ricardel was made in a statement by White House spokeswoman Sarah Sanders on Wednesday.
The spokeswoman added that Mrs Ricardel "will continue to support the president".
According to US media reports earlier this week, Mrs Trump and Mrs Ricardel quarrelled over seating arrangements on her plane.