Jack Keane declined offer to be Defense secretary: report

Retired four-star Army Gen. Jack Keane said he was offered the position of secretary of Defense in Donald TrumpDonald TrumpThe New York Times, other outlets crying 'wolf' over Trump NSA head: DNC hack didn't affect election outcome With Trump political disruption matters more than morality MORE's administration, but declined, NPR reported.

"I was asked to serve, but I'm not able to," Keane told NPR.

"I have some personal issues surrounding the death of my wife recently, and I explained all that to Mr. Trump, and he was very gracious and understanding, and quite supportive."

Keane's wife died in June after battling Parkinson's disease.

Keane, who visited Trump Tower on Thursday, said he recommended retired Marine Corps Gen. James Mattis and former CIA Director David Petraeus for the position.

Trump on Sunday praised Mattis.

"General James 'Mad Dog' Mattis, who is being considered for Secretary of Defense, was very impressive yesterday," he tweeted.

"A true General's General!"

The president-elect has been meeting with several potential Cabinet appointees since his victory.