DC 33 and DC 47, together representing about 13,000 workers in their main bargaining units, have been working without wage increases and under the terms of expired contracts since summer 2009. Nutter is seeking savings in pension, health-care and overtime costs, and the unions have resisted those changes and asked for steeper wage increases.
Regarding the letter, Nutter said his "interests and efforts are the same. . . . We want to have multiyear contracts with wage increases as well as reforms."
"It's top priority for me but it's not just about signing a contract," he said. "Can the citizens of the city afford that contract? How does it impact services that I know the Council members care about for their constituents?"
Nutter last year had to abandon his annual budget address when hundreds of union protesters screamed and blew whistles.
Council President Darrell Clarke has said that won't happen at this year's speech March 6, but he declined to say how he would prevent it.
The Council letter specifically encouraged the mayor to soften his demand for the right to furlough workers up to 15 days per year, which the administration says will only be used during economic downturns.
"Why dig in your heels during for something you do not intend to use?" the letter said.
Nutter said he didn't want to discuss private negotiations in public, but offered this comment: "I understand that is one area of particular concern to the union leadership. I have a couple areas of particular concern with regard to pensions, health care and work-rule changes, so it will all have to be a part of a larger conversation. Everything's on the table."
On Twitter: @SeanWalshDN