Melania and Ricardel reportedly clashed during the first lady's trip to Africa.
Per CNN, a White House official further accused Ricardel of lying about the conflict with the first lady, and of leaking false stories about the first lady following the Africa trip.
She pushed Trump's immigration policies, including funding for his border wall and defended the administration's practice of separating children from parents, telling a Senate committee that removing children from parents facing criminal charges happens "in the United States every day".
On Wednesday, Trump told reporters that "as we make changes, we'll sit down and talk to you about it".
Homeland Security Secretary Kirstjen Nielsen was thought to be out as soon as this week, according to two people with knowledge of the issue, but she is now likely to remain in the post for a longer period because there is no obvious successor in place.
The president (center with Melania Trump right) reportedly wants someone tougher on immigration. Trump is believed to have berated her in front of other cabinet officials over his belief that she did a poor job securing the US-Mexico border, former officials said in a New York Times report. The official, who spoke on condition of anonymity to discuss White House personnel matters, said Ricardel then threatened not to send any NSC staff.
The East Wing staff have reportedly complained that Ricardel feuded with them over the use of national security council resources.
Trump canceled a planned trip with Nielsen this week to visit USA troops at the border in south Texas and told aides over the weekend he wants her out as soon as possible, these officials said.
Trump is said to have this weekend told advisers of his plan to get rid of her as Nielsen's one-year job anniversary of December 6 approaches.
At least 18 of those were publicly fired, including the most recent firing of former Attorney General Jeff Sessions.
With the mid-term elections now in the rear-view mirror, the situation in the Trump White House appears to be coming to a head.
Anita McBride, who was chief of staff to first lady Laura Bush, said there's a lesson in the current first lady's public pronouncement.