PROVIDENCE — Providence Mayor David N. Cicilline has resigned as co-chairman of Hillary Clinton’s Rhode Island campaign rather than face a firefighter and police picket at an upcoming fundraiser for Clinton.

Cicilline has also pledged not to attend the fundraiser to be held Sept. 27 in East Greenwich.

The Providence firefighters and police, who are embroiled in years-long contract disputes with the city, vowed in August to picket the event unless Cicilline stepped down as co-chair and promised not to attend.

Weeks of furious behind-the-scenes negotiations followed, according to union officials, and this morning, Cicilline, resigned as chairman of the Clinton campaign in Rhode Island, and this afternoon said he would not attend the fundraiser.

“I learned that the firefighters union are trying to extort from the city and from me agreement to provisions of a contract, which I will not allow,” Cicilline said.

“It was important for me to remove that opportunity from the union leadership, the chance to use my position to in any way undermine my responsibility to the taxpayers of the city.”

Cicilline said that he isn’t worried about the picketing — but he couldn’t allow the police and fire unions to use his position with Clinton as a bargaining chip.

“My decision is not the consequence of fearing the disruption of the event. I’ve had them protest my events. There are signs across the city. I’m used to that.

“The issue is their trying to use my position to extort outrageous demands from the taxpayers of this city,” Once he recognized they were using this event, he said, “I knew I had to step down.”

In an interview earlier today, Cicilline said he would attend the event. But later in the day, he issued a statement saying he would not.

Joseph Rodio, a lawyer representing both the police and fire unions, said that the negotiations go back weeks, and that the deal that was worked out was that Cicilline had to step down and promise not to attend.

If he does attend, Rodio said, the picket is on.

“There were two predicates. If he violated either one, it’s a full-fledged picket,” Rodio said. “If he wants to go, we’re picketing.”

If there is a picket, then Rodio said he has been told that Clinton will not attend — in much the same way that John Edwards cancelled a 2004 campaign visit rather than cross the firefighters’ picket line.

It was “indicated to us that she would not show up if there was a picket. So there wasn’t a choice on his part, in my opinion,” Rodio said.

State Democratic Party Chairman William Lynch said that any prior discussions were confidential, but did allow that it’s unlikely that Clinton would cross the police and fire line.

This isn’t the first time that the union and the city have squared off over campaign visits. In 2004, Vice Presidential candidate John Edwards canceled a speech at the Providence Biltmore Hotel rather than cross a firefighter picket line.

Cicilline said in his letter to Clinton that he plans to continue working on her behalf, and that he looks forward “to working with you on issues ranging from community policing to education reform when you are sworn in as the next President of the United States.”

Clinton’s campaign released a statement in response to the situation yesterday.

“I have tremendous respect for David Cicilline’s integrity and his service to the people of Providence. He is, and will continue to be, someone I consider a friend,” the statement read.

Clinton is expected to fly in and depart quickly after the lunchtime event Thursday, Democratic Party Chairman Lynch said. He added that she knew that the labor situation existed when she decided to come here, and that Clinton and other candidates run into this kind of situation wherever they go.

“Nothing that happens in Rhode Island is unique to Rhode Island, unless you ask someone in Rhode Island. The truth is that these issues occur all over the country. To run into this type of circumstance is not unique to Rhode Island,” Lynch said.