New Orleans Mayor Mitch Landrieu became the latest politician on Tuesday to take aim at embattled Republican presidential candidate Donald Trump, who has been denounced by political leaders across the country for proposing a ban on all Muslim arrivals.

In an emailed statement, Landrieu called Trump’s proposal “absolutely disgraceful” and called on Americans to reject Trump’s “poisonous rhetoric, which is reminiscent of David Duke’s racism.”

Trump’s controversial statements come in the wake of terrorism from jihadist extremist group the Islamic State in Paris and elsewhere, and after suspected IS sympathizers carried out a deadly mass shooting in San Bernardino, California. It also comes a day after President Barack Obama asked the country not to “turn against one another” out of fear.

David Duke, a former Louisiana House representative who unsuccessfully ran for Congress and in the 1992 Republican presidential primary, is infamous for his white supremacist views.

Trump — who has come out swinging against Muslims repeatedly in recent months — has tried to distance himself from Duke, despite the latter’s enthusiastic endorsement of him. Duke called Trump the “best of the lot” of the GOP presidential candidates, according to BuzzFeed.

Later, Trump told Politico he didn’t want Duke’s endorsement, though he also said he didn’t want anyone’s endorsement.

Here's Landrieu's full statement:

“Donald Trump’s comments about Muslims are absolutely disgraceful. As Americans we must reject his poisonous rhetoric, which is reminiscent of David Duke’s racism. Millions of loyal Muslim Americans should not be maligned by the outrageous actions of a few. Muslims are loyal Americans who serve this nation as police officers, firefighters and in the military. We live in a nation where diversity is our greatest strength. Mr. Trump’s brand of politics is dangerous; it makes our nation more dangerous and weakens our ability to defend against terrorists. Together, we can defeat ISIS by strengthening ties with our Muslim friends, not alienating them with ignorant, hateful statements.”

Trump's call to block all Muslims from entering the United States is not only unconstitutional, but also impossible to carry out, legal experts said Tuesday.

Trump's proposed ban, announced to cheers at a rally in South Carolina Monday, would apply to immigrants and visitors alike, a sweeping prohibition affecting all adherents of a religion practiced by more than a billion people worldwide.

Beyond inciting condemnation from Republican presidential rivals, GOP leaders and others, legal and immigration experts said Tuesday that Trump's proposal violated the Constitution's equal protection clause and freedom of religion granted under the First Amendment.

The Associated Press contributed to this report.