Biden skipping conference to avoid crossing picket line

Presidential spokesman Robert Gibbs said the Obama administration will redouble its efforts to work with the nation's mayors in other ways, including a fresh invitation for the mayors to come to the White House.

Even as the White House was announcing its decision, the mayoral group's website promoted that its confirmed guests included Biden, senior Obama adviser Valerie Jarrett, Attorney General Eric Holder, Commerce Secretary Gary Locke, Labor Secretary Hilda Solis, and other administration officials.

"While this administration is taking no position on the circumstances of the dispute itself, we have always respected picket lines, and administration officials will not cross this one," Gibbs said.

The labor strife comes from a years-long conflict between Providence Mayor David Cicilline and local firefighters over contract matters. Cicilline accused the union of "political extortion" and said it would not work.

"This is a once-in-a-lifetime opportunity for Providence to shine on the national stage, highlighting all the good things about our city, and all the accomplishments of our community," he said in a statement. "But this opportunity is now in jeopardy. . . . It also means that the national media coverage will reinforce the worst stereotypes about Providence, our state, and the labor movement in general."

The firefighters' international association, based in Washington, praised the White House.

"We appreciate the Obama administration's support of firefighters," said the group's president, Harold Schaitberger. "This is another example of the administration's unqualified support for workers and organized labor."