Environment Minister Phil Hogan pulled the funding for the service run by the Irish Deaf Society under a scheme run by his department.
The cut puts a halt to 11 years of services for the deaf population of Ireland, with an estimated 5,000 people affected.
Chief executive of the IDS Eddie Redmond said he was “stunned” by the cut and said the closure leaves a “gaping hole” in services which sought to bridge a socio-economic divide between deaf people and their hearing counterparts.
“We are absolutely stunned by this outcome,” said Mr Redmond. “We are seriously concerned for the welfare of deaf community members, many of whom have come to depend on the advocacy service as the only viable service for them, with other services inaccessible due to Irish Sign Language being their first and in some case only language.”
The IDS is appealing the decision through Pobal, which manages funding programmes on behalf of the State and the EU.
Fianna Fáil spokesman on disabilities Colm Keaveney said Mr Hogan had left a vulnerable section of Irish society “high and dry. IDS provides an invaluable service to deaf people, including helping with access to education, healthcare and offering avenues to employment,” he said.
A total of 55 groups received funding of just over €8m under the scheme.