RTÉ is looking to cut 250 members of staff through voluntary redundancy.
Director-general Dee Forbes told employees today that "painful choices" lie ahead to make the broadcaster smaller and more efficient.
RTÉ has said voluntary exit and early retirement schemes will open next week when staff will receive details of the packages available.
It is thought around 250 people will leave the organisation.
Ms Forbes admitted there will be "painful choices", as well as "an exciting future".
"Our financial situation requires us to reduce costs and employee numbers. We need to become a smaller, more efficient organisation. That will mean that we will lose some colleagues," she said.
Ms Forbes added: "It will also affect the scope of what we are able to do. Critically, we must ensure that we are investing in the programmes, reporting and content valued by our audiences."
RTÉ employed 1,984 people in 2016 its annual report shows. A total of 278 of this number were part-time or casual staff.
The scheme is part of a broader restructuring of RTÉ first announced in March.
Mr Forbes said "sitting still was not not an option in what is a radically changing market"
She added that RTÉ will be a "better organisation" fort the restructuring.
"In a world of fake news, misinformation and opinion; diminishing trust in public institutions and where the media environment is increasingly dominated by international programming and perspectives, it has never been more important that RTÉ continues to have a unique and invaluable role to play," she continued.
"I believe that role is worth defending, worth supporting and worth renewing. The changes announced today will help us to fulfil this role."