Police Commissioner Bill Bratton chastised the heads of the police unions Monday evening, saying their barbs against the mayor are unnecessary while deeming the most recent criticism a "cheap shot."

In the latest back-and-forth, Sergeants Benevolent Association president Ed Mullins called Mayor Bill de Blasio a "nincompoop," according to reports, objecting to the mayor's phrasing when he condemned an attack on officers during Saturday Brooklyn Bridge protests by saying "protesters allegedly assaulted" the officers.

Recently, Pat Lynch, the president of the Police Benevolent Association, posted a waiver he asked officers to sign, telling de Blasio and City Council Speaker Melissa Mark-Viverito they were not welcome at police funerals.

"I'm very embarrassed for the president of the Sergeants Benevolent Association for the cheap shot. The mayor misspoke in terms of his use of the term 'allegedly,'" Bratton said at an unrelated news conference at police headquarters. "This constant effort on the part of the ... professional leadership of some of our unions to attack this mayor was a cheap shot, that's what that one was."

Bratton said the "personal attacks" and "name calling" are unnecessary. And a funeral, especially, is not the place to engage in politics.

"Police funerals, and I've unfortunately been to all too many of them in my 44 years, are really the most solemn thing we do," he said. "They certainly have their grievances, but those grievances need to be dealt with at the bargaining table, need to be dealt with without personalizing. And that's a deeply personal attack to make that we're going to bar you, we're going to encourage the family of a deceased officer, from allowing the mayor of the city of New York."

Representatives for the SBA and the PBA did not immediately respond to a request for comment.