(CNN) -- Ret. Vice Adm. Bob Harward has turned down President Donald Trump's offer to be national security adviser, sources told CNN Thursday.
A friend of Harward's said he was reluctant to take the job because the White House seems so chaotic. Harward called the offer a "s*** sandwich," the friend said.
Earlier this week, Trump fired Michael Flynn as national security adviser. Trump has named Ret. Lt. Gen. Joseph Keith Kellogg, who worked under Flynn until his resignation, the acting national security adviser.
A senior Republican familiar with the process said "a question of clarity regarding the lines of authority" was central in Harward's decision.
"I wouldn't call it a disagreement as much as questions that could not be resolved to his comfort level," the Republican said.
White House press secretary Sean Spicer, responding to reports earlier in the day that Harward was out of the running, said he was unable to confirm and was "still not entirely sure that's true." A White House official later told CNN Harward turned down the role for financial and family reasons.
Asked if there was a candidate for national security adviser in sight, the official replied, "Not that I'm aware of."
Harward served as Mattis's deputy when he was commander of US Central Command, which oversees US military operations in Iraq and Afghanistan.
Flynn was forced to resign his position in the Trump administration after reports said he discussed sanctions with the Russian ambassador before Trump was inaugurated and misled Vice President Mike Pence about the conversation. The White House said Flynn's omission about the details of his conversation led to an erosion of trust between Flynn and the President, prompting Flynn's exit.
Following a more than 30-year military career, Harward became chief executive of defense giant Lockheed Martin's United Arab Emirates division.
Harward was already familiar with the role of national security adviser and the work of the National Security Council, having previously worked on the NSC's counterterrorism office from 2003 to 2005 during President George W. Bush's administration.
After Flynn's resignation, Harward's name floated to the top of lists for potential replacements, alongside acting adviser Kellogg and retired Army Gen. David Petraeus, who pleaded guilty in 2015 to mishandling classified information after he shared sensitive material with a woman with whom he was having an affair.
Ret. Army Maj. Gen. James "Spider" Marks, a CNN military analyst, called Harward an "incredibly talented guy" in an interview with CNN's Erin Burnett on "OutFront.
Marks said he didn't want to speculate why Harward turned down the job, but said turmoil in the White House was likely a contributing factor.
"I'm sure Bob looked at this, Adm. Harward looked at this, and said, 'Look there's a lot of forming and storming going on right now.'"
CNN's John King, Jake Tapper, Eli Watkins and Allie Malloy contributed to this report.
The-CNN-Wire™ & © 2017 Cable News Network, Inc., a Time Warner Company. All rights reserved.