Delaney has been in his role as Chief Executive since 2005, having previously served as Treasurer.
The Waterford native was voted on to the FAI Board of Management in 1999, and was elected as Treasurer in 2001.
The announcement came after Ireland beat Gibraltar 1-0 at the Victoria Stadium on Saturday.
Delaney has come under pressure to explain a 'bridging loan' he facilitated to the FAI in 2017 after a report in The Sunday Times. Fine Gael TD Noel Rock, who is a member of the Oireachtas Sports Committee, was highly critical of Delaney, saying: "It’s not good enough to say 'there was a cash flow issue' - why was there a cash-flow issue? Why are we paying €360,000 per annum for a chief executive of an organisation that seems forever mired in controversies, disputes and now, it appears, financial mismanagement.
"It’s nothing personal, I’m open to hearing his explanations with an open mind, but from the documents I have, and FAI sources I’ve spoken to… it’s not good enough," he added.
Minister for Justice, Charlie Flanagan, also called for clarity from the organisation, telling the Irish Examiner: "I’d like to hear from John Delaney and the FAI. The Dáil committee will deal with that and I am not a member of the committee but I will be tuned in to see what the answers are.
“Any organisation that gets any form of State funding should be required to produce full and detailed accounts on an annual basis and the FAI is no different.”
Delaney was due to appear before the Oireachtas Sports Committee on April 10th.
A statement from the FAI read, in part: "The Board of the Football Association of Ireland has adopted a review of its senior management structure that will see Chief Executive Officer John Delaney move to a new position of Executive Vice-President with immediate effect.
"Chief Operating Officer Rea Walshe has been appointed to the role of interim CEO by the Board as the recruitment process begins for a new Chief Executive Officer"
More to follow...