According to The Washington Post newspaper, Trump has already informed his advisers about the decision and started looking for a replacement.
Over the past few months, the US president has been expressing his discontent with Nielsen's immigration policy and wants to replace her with someone who would be more eager to implement his ideas on the issue, the media said.
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According to Nielsen's colleagues, the secretary has been dissatisfied with her job for several months but does not want to quit until December 6 — one year since taking the position.
More than 50 members of the Trump administration have been fired or resigned since the president took office in January 2017, according to CNN.