Pete Buttigieg, the mayor of South Bend, Indiana, and a 2020 Democratic presidential hopeful, on Sunday accused President Donald Trump of leveraging his privileged background to avoid military service, calling Trump’s 1968 medical deferment during the Vietnam War “an assault on the honor of this country.”

“There is no question, I think, to any reasonable observer that the president found a way to falsify a disabled status, taking advantage of his privileged status in order to avoid serving,” said Buttigieg, an Afghanistan War veteran, during an interview on ABC’s “This Week.”

He continued: “You have somebody who thinks it’s all right to let somebody go in his place into a deadly war, and is willing to pretend to be disabled in order to do it. That is an assault on the honor of this country.”

When he was draft-eligible for the Vietnam War, Trump received deferments because a doctor diagnosed him with bone spurs in his feet. The daughters of a podiatrist who diagnosed Trump with the foot condition in 1968 said in December that it was done as “a favor” to Trump’s father, Fred Trump. “What he got was access to Fred Trump,” Elysa Braunstein told The New York Times.

In his interview on ABC, Buttigieg also criticized Trump for reportedly considering pardons for several U.S. service members accused of war crimes, calling the idea “slander against veterans that could only come from somebody who never served.”

The 37-year-old Democrat ratcheted up his attacks on Trump ahead of the Memorial Day weekend, mocking the president’s past role on the reality TV show “Celebrity Apprentice” in an interview with The Washington Post.

“I don’t have a problem standing up to somebody who was working on Season 7 of ‘Celebrity Apprentice’ when I was packing my bags for Afghanistan,” Buttigieg said, referring to the president’s past role on the reality TV show.

Trump, meanwhile, has taken a more dismissive attitude toward the millennial presidential candidate. The president has mocked the pronunciation of Buttigieg’s last name during several campaign rallies, and he has likened him to the big-eared Mad magazine mascot Alfred E. Newman.