SPRINGFIELD -- Gov. Pat Quinn said Tuesday he's in the process of sending layoff notices to about 2,600 employees throughout state government, from state troopers to human services workers.

Quinn said notices will be mailed, and the actual layoffs will be completed in the coming months.

The layoffs are part of Quinn's proposed cuts to state government during what he calls a "financial calamity" facing the state.

"We can't spend money we don't have," Quinn told reporters in Chicago.

The governor has asked lawmakers for more money via an increase in the state's income tax rate, but they haven't agreed. Instead, on Tuesday, Quinn vetoed a portion of the state budget approved by lawmakers last month, saying more spending needs to be cut.

In addition to the 2,600 layoffs, Quinn wants workers to take 12 unpaid furlough days. That plan is subject to negotiations with the unions that represent state workers.

Quinn said if the unions don't agree to furloughs, there could be about 2,500 more layoffs.

A spokesman for the state's largest employees union said they haven't seen the layoff notices yet, and the state hasn't made arrangements to negotiate the furloughs.

Anders Lindall, spokesman for the American Federation of State, County and Municipal employees, said they oppose furloughs because people are more in need of state services like food stamps during the recession.

"They would worsen the delays and backlogs and overtime costs," Lindall said.

Quinn has said even with a tax increase, cuts will have to be made. State Rep. Brandon Phelps, D-Harrisburg, said he wants to know specifics before he'd vote to raise taxes.

"What other cuts are there going to be?" he said.

Quinn implored lawmakers to cut the budget they already approved, but in his veto, Quinn could have made those cuts himself. That would have left lawmakers with clear decisions about what cuts they wanted to override.

"I think it would have least allowed some very specific action," said state Sen. Dan Rutherford, R-Chenoa.

Illinois has been without a budget since July 1, leaving state government with minimal authority to pay its bills. Lawmakers are set to return to Springfield Tuesday, when they'll have the option of overriding Quinn's actions.

Where the layoffs will be made

Gov. Pat Quinn has started the process of laying off 2,600 state workers in order to deal with the state's deep money troubles. Here's where some of the proposed layoffs would come from:

- Department of Human Services: 870 layoffs

- Department of Healthcare and Family Services: 66 layoffs

- Department of Corrections: More than 1,000 layoffs

- Department of Juvenile Justice: more than 105 layoffs

- Department of Natural Resources: 67 layoffs

- Department of Revenue: 69 layoffs

- Illinois State Police: 303 layoffs