Adding yet another general to his administration, President-elect Donald Trump is expected to tap retired Marine Gen. John Kelly as his choice to lead the Department of Homeland Security.

Kelly told Fox News Trump already has asked him to serve in the DHS position.

“I have been asked and would consider it an honor,” he said.

Kelly would be the third general Trump has picked for his administration, after announcing James Mattis – who along with Kelly is a four-star general -- as his pick for Defense secretary. Trump also announced in November that retired Gen. Michael Flynn would be his national security adviser.

Kelly retired from the Marine Corps earlier this year after leading U.S. Southern Command for three years, during which he was involved in the oversight of the detention center at Guantanamo Bay and the southern border.

Kelly was picked by Defense Secretary Robert Gates to serve as his senior military adviser and then served in the same position under Leon Panetta before moving to Southern Command.

Kelly complained at his last Pentagon press conference in January that after 40 years as a Marine he had the authority to watch drug dealers heading to the border by sea, but he could not disrupt them. He is believed to have a good relationship with current DHS Secretary Jeh Johnson, with whom he served as Pentagon general counsel.

He served three tours in Iraq, and holds the somber distinction of being the most senior military officer to lose a child in combat in Iraq or Afghanistan. His son, Marine 2nd Lt. Robert Kelly was killed in November, 2010, in Helmand Province, Afghanistan.

Known as an outspoken but loyal commander, Kelly will be first to lead the department who is not a lawyer and the fifth overall. The department was formed after the 9/11 terror attacks in order to help foil future attacks on the American homeland.

Sources say Trump has settled on Kelly for the role, and is expected to name him in the next few days. Kelly’s selection will require confirmation by the Senate.

Immigration enforcement is a familiar issue for Kelly, and a big part of the DHS portfolio. Southern Command, which is based in South Florida, regularly works with DHS on missions to identify and dismantle immigrant smuggling networks. And it has partnered with Immigration and Customs Enforcement in an operation targeting human smuggling into the U.S. and helped with the rescue of children arriving alone at U.S. borders.

While Trump has tapped military officials for key appointments, doing so can also bring complications. Gen. Mattis will need to secure a waiver from Congress in order to be considered due to a requirement that military officials be out of service for seven years before being secretary of Defense.

Trump, meanwhile, said Wednesday that he has taken, and acted on, advice from President Obama on who he should appoint to various positions in his administration.

“I have asked him what he would think of this one and that one,” Trump said on NBC's "Today" show. “I would say that, yes, I take his recommendations very seriously and there are some people that I will be appointing, and in one case have appointed, where he thought very highly of that person, yes.”

While he did not go into specifics, he said that he likes Obama "as a person" despite the brutal criticism he leveled at the president on the campaign trail.

"I will say this, I've now gotten to know President Obama. I really like him. ... I can't speak for him, but we have a really good chemistry together. We talk,” Trump said.

A coziness between current and former presidents is not unusual. President George H.W. Bush wrote President Bill Clinton a warm note when Clinton took office, while President Obama has repeatedly spoken of how accommodating President George W. Bush's team was to Obama in the lead-up to him taking office in 2009.

Fox News’ John Roberts and Jennifer Griffin and The Associated Press contributed to this report.