HARTFORD — Legislative leaders said Wednesday they feel betrayed by acute care hospitals across the state appealing rate increases that were agreed upon by the Connecticut Hospital Association and the administration.

Martin Looney and Len Fasano, the Democratic and Republican Senate leaders, issued a statement calling it "a thoroughly disappointing and shocking development." The lawmakers said they fear this "about-face" will endanger the state's pending application for federal reimbursement, which stems from a complicated formula tied to the hospital rates.

The hospital association has been at odds with the state since 2013 about whether state Medicaid reimbursement rates cover hospitals' costs. On Wednesday, it denied its members have reneged on any agreement with the General Assembly and Democratic Gov. Dannel P. Malloy. In fact, the association said it sent a document to the federal Centers for Medicare and Medicaid Services, supporting the state's application for the reimbursement.

"The rate appeals represent hospitals going through a standard process to protect their rights," said the association, which has tried to seek a settlement with the state to cover past financial losses due to insufficient rates.

Ben Barnes, Malloy's budget secretary, informed lawmakers Wednesday that most of the state's acute care hospitals have sent letters to the Department of Social Services, appealing rate increases. He also voiced concern that the appeals "may hinder" the state's pending application and put the state "at risk of significant financial harm."