Here's one endorsement Republican frontrunner Donald Trump probably doesn't want: The Ku Klux Klan.

David Duke, a former Klansman who made two failed presidential bids in the late 1980s and early 1990s and was almost elected Louisiana governor, is throwing some support behind Trump, BuzzFeed reported Tuesday.

On his radio program last week, Duke said Trump "understands the real sentiment of America" and praised the real estate mogul for "talking about the immigration issue."

"He has really said some incredibly great things recently," Duke said. "I really like the fact that he's speaking out on this greatest immediate threat to the American people."

While Trump's focus on immigration policy has indeed proved popular among Republican voters, many of his remarks — such as calling Mexican immigrants drug runners, criminals and rapists — have drawn fierce criticism from rival candidates within his own party and liberals alike.

While Duke said Trump was "the best of the lot," he also said Trump wasn't trustworthy.

"Although we can’t trust him to do what he says, the other Republican candidates won’t even say what he says," Duke said. "So he’s certainly the best of the lot. And he’s certainly somebody that we should get behind in terms...raising the image of this thing."

Listen to the full audio of Duke's comments below: