President Trump's claim to have called "virtually" every Gold Star family during his tenure prompted the White House to assemble a list of the fallen.

An internal Defense Department email shows that the White House team reacted to Trump's comment by asking for a list of "Condolence Letters Since 20 January 2017" from the Pentagon "ASAP." The scramble came amid questions about why Trump delayed commenting publicly on the death of four soldiers ambushed while advising partner forces in Niger.

"The email exchange, which has not been previously reported, shows that senior White House aides were aware on the day the president made the statement that it was not accurate — but that they should try to make it accurate as soon as possible, given the gathering controversy," according to Roll Call, which obtained the email.

Trump broached the topic of presidential phone calls to the families of fallen soldiers in an apparent effort to deflect criticism of his silence about the Niger ambush. "President Obama and other presidents, most of them didn't make calls," Trump said during a press conference at the White House. "A lot of them didn't make calls."

He added that Obama "probably did sometimes" before suggesting he relied upon the Defense Department to tell him about past practices.

Former Obama officials shot back. "To say president obama (or past presidents) didn't call the family members of soldiers KIA — he's a deranged animal," Alyssa Mastromonaco, former White House deputy chief of staff for operations, tweeted.

Trump defended himself by invoking White House chief of staff John Kelly, a retired Marine Corps general whose son was killed in action in 2010. "I think I've called every family of someone who's died," Trump said on Fox News radio. "As far as other representatives, I don't know. You could ask Gen. Kelly, did he get a call from Obama?"

Kelly confirmed that Obama had not called, but defended his former commander-in-chief and noted that he had advised Trump not to call Gold Star families. "That was not a criticism. That was just to simply say, I don't believe President Obama called," Kelly told reporters at the White House. "That's not a negative thing. I don't believe President Bush called in all cases. I don't believe any president, particularly when the casualty rates are very, very high – that presidents call. But I believe they all write."

The controversy distracted from questions about the operations in Niger. Kelly confirmed that an investigation is underway, but declined to share any details about the ambush that he may have learned. Congressional investigators are asking the Pentagon for information about whether an "intelligence failure" or some logistical problem exposed the patrolling Americans to additional danger.

"The war is headed to Africa," Sen. Lindsey Graham, R-S.C., said Friday after a meeting with Defense Secretary Jim Mattis. "It's beginning to morph. As we suppress the enemy in the Mideast, they are going to move. They are not going to quit."