"Trump canceled a planned trip with Nielsen this week to visit US troops at the border in South Texas and told aides over the weekend he wants her out as soon as possible", The Washington Post reported, citing five current and former White House officials.
She served under National Security Advisor John Bolton as his second in command but clashed with White House staffers and first lady Melania Trump's staff for her trip to Africa, according to NBC News.
Nielsen has been in the White House for less than a year and has spent her time focusing on a number of issues, including border security. The other source said that Melania Trump felt that Ricardel tried to short-change the first lady in terms of USA government resources allocated to support her Africa tour.
"There have been instances where the East Wing staff were not treated as equals to the male-dominated decision makers in Chief Kelly's office", a White House official told the network.More news: Pippa Middleton names son and gives him a family connection
The other source said that Ms Trump felt Ms Ricardel tried to short-change the first lady in terms of United States government resources allocated to support her Africa tour.
Ricardel has denied trying to undermine Mattis.
Mum-of-one Melania can speak more languages than any other First Lady before her: English, French, German, Italian, Serbian and of course her mother tongue, Slovenian.
The first lady took the issue to the president as they traveled to France over the weekend, and on Tuesday firmly called for Ricardel to lose her job.
The president (center with Melania Trump right) reportedly wants someone tougher on immigration.
The sources said that Melania Trump explicitly asked the president to oust Ricardel after their dealings over the Africa trip "didn't go well".More news: Chiefs-Rams game in Mexico City in jeopardy over field conditions
Ricardel was also believed to have had a dislike of Defence Secretary Jim Mattis, current and former officials have told Reuters.
That clash also involved Ms. Nielsen, according to White House sources.
The constant fighting almost led to Nielsen's resignation, but she was talked into staying be her mentor John Kelly.
Homeland Security Secretary Kirstjen Nielsen is reportedly being forced out of her position soon, sources said in a Washington Post report.
It's not clear who would succeed her, or whether the White House has potential replacements lined up.
While Nancy Reagan was reportedly influential in the ouster of former President Ronald Reagan's chief of staff, Donald T. Regan, in 1987, she did so behind the scenes.More news: EPL: Arsenal confirm second Welbeck surgery