Budget cuts by state lawmakers are threatening the effort to reform the Department of Children and Families, an agency under federal court oversight for failing too many abused and neglected children, the court monitor reported Tuesday.

“It is very concerning that the state has chosen to reduce and freeze staffing without acknowledging that the complexity of … staff caseloads have increased significantly,” Raymond Mancuso wrote in his quarterly report on the agency. “The lack of sufficient staffing will impact Commissioner [Joette] Katz’s ability to fully implement and sustain the important and long overdue changes.”

Mancuso also wrote legislators on the General Assembly’s budget-writing committee asking them to reverse course.

In the last three fiscal years, state legislators and the governor have decided not to provide the funding for the agency to fill the 270 positions that became vacant from people retiring or quitting their jobs.

And it may not end there.

Gov. Dannel P. Malloy’s proposed budget for the next two fiscal years recommends the state save $4.6 million by shedding 40 more positions. The administration reports such a reduction is warranted because the number of children in state custody is decreasing due to agency initiatives that divert less-serious cases to nonprofit providers.

The agency’s budget over the last two years has decreased by at least $26.4 million, a 3 percent reduction. This was largely the money that the agency was able to save by removing fewer children from their families and moving children back home from costly out-of-state facilities and large-group homes.

The problem is, however, that the agency was counting on that money to carry out the commissioner’s plans to provide community-based services and help open private facilities for children who otherwise would be sent out-of-state.

Mancuso wrote legislators saying that efforts to improve are “being severely compromised by well documented resource deficiencies… Service gaps, waitlists and service coordination issues have been exacerbated.”

These shortfalls include providing services to help families overcome homelessness or treat mental health, substance abuse, or domestic violence. Of the 54 cases reviewed by the court monitor between October and December of last year, he found 279 instances of children not being properly cared for.

The agency does have a plan to expand services in some areas, but the monitor warns it’s not enough.

“The services being implemented will not be sufficient to meet the core service needs of the children served by the Department,” Mancuso wrote.

The staffing levels at the child welfare agency — which have dropped by 8 percent over the last three fiscal years — have also drawn concern from the union representing social workers in the state.

With the shift to divert the less-severe cases to nonprofit providers, the agency’s social workers are left with the same caseloads but with more children with significant needs.

“Every case they get is a difficult case now… There is no let up and some of the needs are not getting met, and it’s not because [social workers] aren’t trying. They are doing what they can,” said AFSCME Local 2663 President Paul Lavallee, whose union represents 2,500 workers in human and social services.

It’s a problem Katz is well aware of.

“It’s definitely more intense for them. There’s no fluff,” she said during a recent interview. “What they are left with are kids coming into care that are more complex, and we are also demanding more of our social workers because of our changes in practice.”

The agency has begun changes that require social workers to arrange visits to homes (and show up unannounced only if there are safety concerns) and create team meetings with a child’s family to strategize how to improve the child’s situation, all of which are more time consuming.

“Even though the numbers are down, their workload and the intensity of their workload has not diminished. I would say the opposite. I would say it has increased,” Katz said.

But she added that her hands are tied in providing them relief.

“There’s not a lot, frankly, that we can do. Our funding is our funding, particularly with the budget being what it is and all the vacancies being swept” by lawmakers to save money, she said.

Connecticut’s efforts to keep children with their families and to avoid placing them in costly group homes follows the lead of other states. However, the Anne E. Casey Foundation, a national nonprofit that helps states improve their child welfare systems, reports that, for it to be successful, the state must resist raiding the department’s savings.

The reinvestments made by New York City and states such as Maine, Virginia and Louisiana have covered the costs of providing more health, behavioral, respite and educational services in the community. By reinvesting their savings, the states have had to remove fewer children from their families, placing them in state custody. Virginia, for example, saved $60 million by lowering reimbursements for large-group homes and reinvesting $15 million of that in higher reimbursements for community-based services, according to the Casey Foundation.

Connecticut’s DCF is well on its way to end 20 years of federal oversight with significant increases in the number of children staying with their families and a reduction in the use of group homes, but Mancuso writes that is being threatened by the budget cuts.

“The ability to achieve the Exit Plan goals in a timely manner is being severely compromised,” he wrote legislators.

Sen. Danté Bartolomeo and Rep. Diana Urban, the co-chairs of the legislature’s Children’s Committee, were not available Tuesday afternoon for comment.