The 49-year-old has being involved with the OCI since 2005 and up until as late as August, had been tipped to eventually take over as president of the organisation.

Temporarily stepped aside OCI president Pat Hickey, who was arrested by Brazilian police in relation to alleged mis-selling of tickets for the Olympic Games in Rio de Janeiro, had personally backed Mr Delaney to succeed him.

Mr Hickey remains in Rio since his arrest by Brazilian police during the Olympic Games, where he is continuing to fight to clear his name.

In his statement tonight, Mr Delaney said having given the matter careful consideration, he has made the decision to step down as the FAI's volunteer member of the 13-person OCI committee board, with immediate effect.

"My role as CEO of the FAI is my primary role and priority. I have always been 100% committed to fulfilling my role, my obligations and duties in ensuring the growth and development of football in Ireland, which I will continue to do," he said.

Mr Delaney said that during his time as a member of the OCI executive committee he always looked to the best interests of the Olympic movement, and in recent months he worked extensively with the other OCI committee members to ensure that all proper steps have been taken by the OCI, following the issues that arose in Rio.

"As part of this, I have fully engaged and co-operated with investigations being carried out by Grant Thornton who were appointed to review ticketing arrangements and Deloitte, whose brief is to examine governance issues within the OCI.

"I will, of course, also provide all assistance sought by Mr Justice Carroll Moran as part of the Government appointed inquiry.

"I am fully confident that in due course my position and non-involvement in these matters will be clarified and independently verified on completion of reports carried out by Grant Thornton or Justice Carroll Moran," Mr Delaney said.

Mr Delaney said because of his football commitments he only attended 5 of the 13 board meetings prior to the Olympic Games.

In a statement tonight, the OCI's acting president Willie O Brien said he regrets Mr Delaney's decision to step down.

"This evening I accepted with regret the resignation of Mr John Delaney from his position as vice-president of the OCI.

"I would like to thank John for his hard work and dedication to the Irish Olympic movement in his time as a member of the executive committee, and I wish him well for the future," Mr O Brien said.