The FAI has confirmed that Stephen Kenny's time as Republic of Ireland manager has come to an end.
The decision followed a board meeting and a presentation by CEO Jonathan Hill and Director of Football Marc Canham.
In a statement, the FAI said it came after the conclusion of the Euro 2024 qualifiers.
"Having reviewed the Euro 2024 qualification campaign in its entirety, and recognising how difficult the group was, the results needed to realise our goal of qualification for the tournament were not achieved," it said.
"The board agrees that now is the right time for change ahead of the friendly matches in March and June 2024 and the next Nations League campaign starting in September 2024."
Ireland failed to qualify for Euro 2024.
The team also drew in a friendly with New Zealand at the Aviva Stadium on Tuesday.
FAI CEO Jonathan Hill said: "Over the period of his tenure, Stephen and his staff have worked tirelessly to create the right environment to support the development of our senior men’s team, and we are hugely grateful for that considerable contribution.
"Stephen has also overseen an important period of transition for our senior men's national team and has given debuts to a significant number of new and younger players and this will serve as a solid platform for whoever now takes this group of players forward."
FAI President Gerry McAnaney added that all at the FAI "would like to sincerely thank Stephen and his staff for their hard work, professionalism and unwavering dedication to the team, the fans, and to Irish football".
The FAI said the recruitment process for a new head coach is now underway.