SPRINGFIELD — Gov. Pat Quinn and Illinois' top legislative leaders have agreed on a plan they hope will finally fix the state's massively underfunded employee pension systems.

Although the details of how they propose to address the $97 billion problem remain in flux, Quinn's office said Tuesday that lawmakers could sign off on a plan as soon as early July.

That timetable could be a bit ambitious in a state where efforts to correct chronic underfunding have fallen flat for years because of disagreements between Republicans, Democrats and public-sector labor unions.

The latest push by Quinn and Senate president John Cullerton and House Speaker Michael Madigan to complete a proposal is expected to get under way today when lawmakers return to the Capitol for a one-day special session on pension reform.

Under a roadmap agreed upon by the three Chicago Democrats, the House and Senate would form a special committee to craft the outlines of a pension overhaul.

Possible changes could force state workers, school teachers, members of the General Assembly and university employees to pay more toward their pensions. The proposal also could result in smaller cost-of-living adjustments for retirees.

Under an emerging proposal backed by the presidents of the state's public universities, annual cost-of-living adjustments would amount to half the rate of inflation.

University officials said they hope their proposal will stabilize the state's finances, which could result in fewer cuts to higher education.

"We have to solve this problem," Southern Illinois University president Glenn Poshard told members of a Senate panel Tuesday.

Mike Carrigan of Decatur, president of the Illinois AFL-CIO, told members of a House committee Tuesday that unions representing school teachers, prison guards and university workers continue to favor a plan that is now stalled in the House.

Asked whether the unions would be willing to support a compromise, Carrigan said he would have to talk with other labor leaders.

"I can tell you that would be a very difficult conversation to have with them," he said.

Neither the governor, Madigan nor Cullerton is publicly saying which provisions they favor as they attempt to find common ground on a problem that has resulted in lower credit ratings for the state and a squeeze on other state programs.

"As Governor Quinn has made clear for almost two years now, he will not approve any plan that is not comprehensive and that does not erase the unfunded liability over the next 30 years," spokeswoman Brooke Anderson said.

"You have a lot of different options," Cullerton said.

The agreement on a possible path forward is significant because Cullerton and Madigan have been at odds over how to balance the need to alter pension benefits for current and former employees.

"This is another approach," Madigan spokesman Steve Brown said. "Let's see where this gets us."

I'm the city editor at the Quad-City Times. You can reach me at dbowerman@qctimes.com or 563-383-2450.