CHICAGO – Chicago Mayor Lori Lightfoot pulled out of a virtual roundtable hosted by Crain's Chicago Business to avoid appearing on the same digital stage as Minneapolis Mayor Jacob Frey, who has been a lightning rod for criticism after the police killing of George Floyd, sources told the Chicago Tribune.

Lightfoot had been scheduled to join political consultant David Axelrod "and the mayors of two Midwest cities on Wednesday to discuss how COVID-19 and recent civil unrest will define the future of our nation's cities," according to a since-deleted Crain's Facebook post.

But Lightfoot abruptly withdrew from the event earlier this week, and sources with knowledge of the situation said the mayor's team told Crain's her cancellation was to avoid being on a virtual stage with Frey.

In a brief statement, the mayor's office attributed the withdrawal to a scheduling conflict. Lightfoot said that Frey "has been through one of the toughest situations of any mayor across the country. Soon after the death of George Floyd, I offered him my assistance and that offer still stands."

Crain's Publisher and Executive Editor Jim Kirk declined to comment.

Frey has been roundly criticized since Floyd's killing spurred national protests and civil unrest. After Floyd's death, a Minneapolis police station was burned down and members of the City Council vowed to radically transform the police department.

Frey has opposed calls to abolish police but promised changes to the department and created a task force to look into the issue.

Chicago is the biggest city in the United States not to endorse some form of defunding police.

It's not clear why Lightfoot wouldn't want to share the stage with Frey.

Lightfoot has a long, complicated history in the local police reform movement. She's a former federal prosecutor who headed the board that oversees police discipline and chaired the Police Accountability Task Force formed by former Mayor Rahm Emanuel. But she is often criticized by activists as being pro-police.

For months, Lightfoot has been in a dispute with activists over how a civilian oversight commission of the Police Department would work, with critics wanting more power given to people outside City Hall. She initially promised a new civilian police oversight body within 100 days of taking office.

She also has a combative relationship with the Chicago Fraternal Order of Police, which was recently illustrated by a series of insulting text messages she sent to FOP President John Catanzara calling him a "clown."