Irish Language Commissioner Seán Ó Cuirreáin has said efforts to use Irish in the civil and public service have got progressively worse over the past few years.
Speaking on The Week in Politics, Mr Ó Cuirreáin criticised the recent introduction of a new scheme to increase the number of employees with Irish in the public service.
He said that under the new system it would take 28 years to increase the number of administrative staff with Irish in the Department of Education from 1.5% to 3%.
He said there needs to be a "rethink" regarding the promotion of the Irish language.
Mr Ó Cuirreáin said that his successor should receive guarantees regarding the use of Irish in the civil and public service.
He announced last Wednesday that he was stepping down as Language Commissioner citing concerns about the lack of progress in ensuring that Irish speakers can deal with the State in Irish.