Donald Trump is heading to Phoenix, Arizona, for a Tuesday night rally, but the city’s mayor is making it very clear that he does not want the president there.

Mayor Greg Stanton (D) did not mince words in a Monday Washington Post op-ed, arguing that Trump’s campaign rally was ill-timed and would cause further division. He cited the president’s widely condemned response to this month’s violent white supremacist rally in Charlottesville, Virginia, as a key reason for not visiting the city.

“America is hurting. And it is hurting largely because Trump has doused racial tensions with gasoline. With his planned visit to Phoenix on Tuesday, I fear the president may be looking to light a match,” Stanton wrote. “That’s why I asked the president to delay his visit. It’s time to let cooler heads prevail and begin the healing process.”

Phoenix residents have mounted protests ahead of Trump’s rally.

After last week’s tumult, Trump is expected to galvanize his base in Arizona, particularly by discussing immigration, one of his signature campaign issues.

There is also speculation that he might pardon the infamous former Maricopa County sheriff, Joe Arpaio, who regularly faced accusations of racial profiling immigrants and operated a “tent city” jail known for brutal conditions.

Brian Snyder / Reuters Donald Trump with former Maricopa County sheriff Joe Arpaio, left, in January 2016, when he endorsed the then-GOP presidential candidate.

A prominent Trump supporter, Arpaio was found guilty for criminal contempt last month.

“A pardon of Arpaio can be viewed only as a presidential endorsement of the lawlessness and discrimination that terrorized Phoenix’s Latino community,” Stanton wrote. “Choosing to announce it in Phoenix — especially in the wake of Charlottesville — would add insult to very serious injury and would reveal that the president’s true intent is to further divide our nation.”

Trump has also alienated members of his own party in Arizona, attacking the state’s senators on several occasions. The president has not only criticized Sen. Jeff Flake, he has also expressed support for the senator’s GOP primary opponent. Trump most recently targeted Sen. John McCain when the senator cast the pivotal vote against the GOP’s revised Senate health care bill last month.

Arizona Gov. Doug Ducey (R) is distancing himself from the president, announcing Monday that he would not attend Trump’s rally.