Hartford — Gov. Dannel P. Malloy on Wednesday unveiled $170 million in spending reductions across state agencies, the first part of a plan to close the state’s $365 million shortfall in the current year’s $20 billion budget.

Malloy’s office released a list that includes nearly $161 million worth of cuts to executive branch agencies. Malloy’s budget director, Ben Barnes, said legislative leaders have agreed to $3 million in reductions while the Judicial Branch has agreed to $5.75 million.

While it’s up to state agencies to administer the reductions, Barnes said, no layoffs are expected. Even though a four-year, no-layoff agreement was reached in 2011 with the state employee unions as part of a labor concession deal, new hires and non-unionized state employees are still vulnerable to losing their jobs. Barnes said the administration will stick with its plans to hire “critical replacements” needed for vacant positions.

The plan includes nearly $33.5 million in cuts to state employee fringe benefits costs. Barnes said he believes that cut can be absorbed because expenses are less than originally budgeted.

The cuts run the gamut, paring funds for everything from local arts organizations to mosquito control.

They include a $33,957 cut for the governor’s office, a $21.3 million cut at the Department of Developmental Services, and a $32.2 million reduction for the Department of Social Services, an agency that has experienced growing demand. Funding for aid to families, as well as programs serving the elderly, homeless and children were all affected.

“Many of these cuts are very difficult to make, especially now when so many residents continue to struggle in a tough economy,” Barnes said. “But as painful as they are, cuts are necessary to keep this year’s budget in balance. State government needs to live within its means.”

The University of Connecticut is facing a $10.3 million hit. President Susan Herbst said the cut was not a surprise.

“My approach in this instance will be to protect what is most vital us: our core academic missions of teaching, learning and research, including the much-needed faculty hiring initiative that is under way,” she said in a message to the UConn community.

The state’s budget-cutting, however, is expected to get even more painful.

The spending reductions announced on Wednesday represent only what Malloy, using his statutory authority, can cut on his own. He’s allowed to rescind up to 5 percent of any budget line and 3 percent of any fund without legislative approval.

Malloy and state lawmakers now intend to work on a plan that addresses the remaining $195 million of the current fiscal year’s deficit. Roy Occhiogrosso, the governor’s senior adviser, said that proposal is expected to be ready sometime in the next couple of weeks, requiring legislators to return for a special session vote. Malloy has said he will not raise taxes to cover the current year’s red ink.

Senate Majority Leader Martin Looney, D-New Haven, promised the latest deficit will be addressed before the end of the year. The new legislative session opens on Jan. 9.

“Just as we did two years ago when we worked to erase a $3.65 billion structural deficit, we are committed to working with Governor Malloy to reduce spending and make the difficult but essential choices necessary to balance the state’s budget before the New Year,” he said.

Meanwhile, Malloy needs to present a new two-year budget to the General Assembly by February. The new fiscal year, which begins on July 1, is expected to be about $1.2 billion short. Malloy has said he doesn’t intend to raise taxes to cover that deficit as well.

“This governor inherited an enormous mess,” Occhiogrosso said. “It took 20 years to dig that hole. It’s going to take us more than 20 months to dig out of it.”