The Rev. Al Sharpton said on Tuesday that he would not deliver the eulogy for slain New York City Police Officer Randolph Holder because he feared police union leaders would use his presence to turn the funeral into "some kind of confrontation."

The decision by the civil rights activist and long-time critic of the NYPD was announced in an open letter emailed to media, which cited reports criticizing his planned role at the funeral scheduled for Wednesday. It came hours after Holder's fiancée was quoted in the New York Post as saying the officer detested Sharpton.

In the Post story, Holder's fiancée Mary Muhammad was quoted as saying on Monday, "He didn't like [Sharpton]. He wasn't a fan. So I don't know why [Sharpton] is speaking.''

Holder, 33, was shot to death last week while on patrol in the city's East Harlem neighborhood. He is the fourth New York City officer killed in the line of duty in the last 12 months.

The email included a letter, which was addressed to Holder's father, and a photograph of the funeral program with Sharpton listed as the eulogist. Sharpton said over the weekend that he had been invited to the funeral by Holder's father, a former police officer in his native Guyana.

Holder was killed by a single shot to the head on Oct. 20. The suspect charged in the murder, Tyrone Howard, 30, is due in court on Tuesday.

"I thought my coming might give a sense of unity in the city; that we can disagree on cases and on policies but that we are united that the senseless and ruthless killing of officers like your son must be denounced," Sharpton said in the letter.

"It is clear though after reading several articles that some union leaders and some others want to turn your and your pastor's noble efforts into some kind of confrontation or sideshow," he said.

The New York Daily News on Sunday quoted Ed Mullins, president of the Sergeants Benevolent Association (SBA), as saying that inviting Sharpton was "an ironic twist. Maybe the family doesn't understand his history with the NYPD. The city is divided because of people like Sharpton."

SBA spokesman Jordan Bieber said on Tuesday that Mullins was only expressing surprise at the invitation."This is one of our fallen brothers and our focus is on Officer Holder and his family. We would never do anything to interrupt that because Al Sharpton is giving a eulogy," Bieber said.

(Additional reporting by Barbara Goldberg; Editing by Toni Reinhold)