San Antonio Spurs coach Gregg Popovich, who has been vocal about President Trump's behavior, lashed out Monday, calling him a "soulless coward" for lying about former presidents not calling families of fallen soldiers.

Trump, while defending his slow response to the deaths of four U.S. soldiers in Niger earlier this month, said that most of the presidents who came before him never called the families of service members killed in action.

“If you look at President Obama, and other presidents, most of them didn’t make calls. A lot of them didn’t make calls," Trump said Monday. "I like to call when it's appropriate, when I think I am able to do it."

Popovich on Monday told Dave Zirin, sports editor at The Nation, that Trump was a "soulless coward" and wanted to make sure the comments were "on the record."

According to the story, Popovich said: "I’ve been amazed and disappointed by so much of what this President had said, and his approach to running this country, which seems to be one of just a never ending divisiveness. But his comments today about those who have lost loved ones in times of war and his lies that previous presidents Obama and Bush never contacted their families, is so beyond the pale, I almost don’t have the words. "This man in the Oval Office is a soulless coward who thinks that he can only become large by belittling others. This has of course been a common practice of his, but to do it in this manner–and to lie about how previous Presidents responded to the deaths of soldiers–is as low as it gets. We have a pathological liar in the White House: unfit intellectually, emotionally, and psychologically to hold this office and the whole world knows it, especially those around him every day. The people who work with this President should be ashamed because they know it better than anyone just how unfit he is, and yet they choose to do nothing about it. This is their shame most of all."

Popovich has been openly critical of Trump before. During the Spurs' media day, Popovich told reporters that the United States is currently "an embarrassment in the world."

"You've got a choice," Popovich said. "We can continue to bounce our heads off the wall with his conduct, or we can decide that the institutions of our country are more important, that people are more important, that the decent America that we all thought we had and want is more important, and get down to business at the grassroots level and do what we have to do."

Recent presidents have acknowledged the sacrifice of fallen soldiers in different ways — and usually with little fanfare. President George W. Bush met personally with more than 450 families of service members who died in the Iraq and Afghanistan wars, and wrote to more than 4,000 of them, according to newspaper accounts at the time.

Obama met with families at Dover Air Force Base, where the military mortuary is located, and also wrote letters and made phone calls. In 2011, he reversed a long-standing policy and began sending letters of condolence to families of service members who committed suicide while deployed to a combat zone.

Contributing: Gregory Korte and Heidi M. Przybyla

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