HARTFORD, CT — The threat of up to 4,200 state employee cuts is becoming more real as Gov. Dannel Malloy warned Thursday that layoffs could begin in May unless unions agree to concessions to help balance the state's budget.

Malloy is seeking concessions of $1.57 billion in the next biennial budget, breaking down to $700 million in savings in the 2017-18 fiscal year and $869 million in 2018-19. Absent an agreement with unions, a first wave of more than 1,000 employees could be laid off come May, Malloy said Thursday. The layoff plan also calls for the elimination of more than 120 vacant positions that were in the process of being filled. Both union and non-union employees could be affected. (To sign up for the free Patch newsletter and breaking news alerts, click here.)

Among the 4,200 people who could be laid off: More than 500 prison employees, 400 judicial branch workers and 300 in the Department of Transportation and Department of Mental Health and Addiction. The Department of Children and Families would face 300 layoffs, the University of Connecticut nearly 200 and another 158 at the UConn health center.

Savings for the plan are projected to be more than $80 million for the first wave of layoffs should they become necessary and $400 million if all the layoffs are completed.

"Talks are ongoing and constructive," Malloy said. "I am optimistic that we will be able to meet our budget challenges as I proposed in February – with labor concessions that reduce our long-term fixed costs related to pensions and benefits for our employees. I believe that the leadership and members of SEBAC are also committed to a negotiated solution. We all hope that our contingency plans will ultimately not be necessary and that the structural solutions Connecticut needs can be found at the bargaining table." On average, the state would save $100,000 per layoff counting salary and benefits, according to the Hartford Courant.

Malloy sent a letter to 12 of the largest executive state agencies calling for them to come up with contingency plans should the layoffs become necessary, according to WFSB. They include the Attorney General's office, the departments of Education, Energy and Environmental Protection, among others.

Malloy's administration notified unions of the plan, which is a step before layoff notices go out. He insisted Thursday that the notification wasn't for leverage and was a legal step that has to be taken if layoffs are possible.