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Speaking as both a 2016 Republican presidential candidate and a good friend of Sen. John McCain, Sen. Lindsey Graham (S.C.) called Donald Trump a "jackass" Monday during an interview with CNN.

Graham was upset over remarks Trump made on Saturday during a GOP political event in Iowa, when he said McCain, who was a POW in Vietnam, was not a "war hero." "I like people who weren't captured, OK?" he added. Those comments were "offensive" Graham said, and didn't put Trump in a good light. "He's becoming a jackass at a time when we need to have a serious debate about the future of the party and the country. This is a line he's crossed, and this is the beginning of the end of Donald Trump...I am really pissed."

Graham wasn't the only one to defend McCain, with even the White House commenting. Press Secretary Josh Earnest said that differences between President Obama and his 2008 campaign rival "have not reduced [Obama's] appreciation for Sen. McCain's remarkable service to the country" and Obama has "deep respect for Sen. McCain’s heroism."