As President Trump threatens more federal incursions into American cities in the name of fighting crime, a group of Democratic mayors huddled on a private strategy call on Wednesday to discuss their plans to fight back.

The call, hosted by the Democratic Mayors Association, represented a new effort from Democratic officials to wrest the narrative from Republicans on public safety, an issue that Mr. Trump has effectively used as a cudgel. It was also an attempt to coordinate on messaging as national Democrats have strained to mount sustained and unified opposition to the Trump administration.

During the call, the mayors in attendance discussed what they saw as an urgent need for Democrats to define themselves as strong stewards of public safety — before Republicans brand them first ahead of pivotal elections, according to a recording obtained by The New York Times.

Mayor Justin Bibb of Cleveland, who leads the association, peppered his remarks with expletives as he urged elected Democrats at all levels of government to seize what he called a “unique opportunity” to go on the offensive with “a serious-on-safety, serious-on-cost messaging strategy.”

“If we’re passive and hemming and hawing about democracy and all that stuff between now and 2026, we’re going to get our asses kicked. We have to start now,” he said.

Mr. Bibb said he planned to discuss the issue with Gov. Andy Beshear of Kentucky, the incoming chair of the Democratic Governors Association, later Wednesday.