Walsh was one of the few women holding a senior role in the Trump White House and was seen as a strong force for organization, though some Trump loyalists viewed her with suspicion because of her roots in the Republican establishment.
A senior administration official told DailyMail.com on Thursday that Walsh had approached senior strategist Steve Bannon about departing the White House to help operate America First, a political nonprofit founded to promote the president's agenda.
White House press secretary Sean Spicer said no more White House staff changes are planned at this time.
It is unclear what the departure means for Preibus, whom some have blamed for Trump's early failures, including the collapse of the GOP health care plan.
Deputy chief of staff Katie Walsh said Thursday she decided to make the move after the Trump-backed health care bill failed last week to amass enough support to clear the House.
Ford recalls 230000 cars over potential engine fires
In October, NHTSA opened a preliminary investigation into 440,000 Ford 2011-2013 Edge SUVs over door latch warning light issues. Ford says it is aware of 29 reports of fire associated with the issue in both the United States and Canada, but no injuries.
Former National Security Adviser Michael Flynn resigned in February after Trump concluded Flynn had given misleading information about contacts with Russian officials. The official said Walsh saw a need to better organize support for the White House's initiatives on the outside. Politico's source for the story was quoted as saying that, "You've got to have somebody from the inside who has the blessing of the man himself" for a move like this.
Making America Great has the financial support of one of Trump's most influential backers, Rebekah Mercer.
Read the latest on Donald Trump's first 100 days in office.
Before serving as chief of staff at the RNC, Walsh worked on a number of political campaigns, including Sen.