Wales' regional rugby chief executive, Stuart Gallacher, has resigned from the boards of the Pro12 and European Cup.
He had represented the four regions - Scarlets, Ospreys, Cardiff Blues and Newport Gwent Dragons - on the boards of the Celtic League and European Rugby Cup Limited.
His move comes amid a dispute between the regions and the Welsh Rugby Union about the future of the game in Wales.
It is understood Gallacher submitted his resignation letter last week.
Regional Rugby Wales - the umbrella body for Wales's four professional sides - is locked in a dispute with the WRU, over funding, the exodus of Welsh players and a possible Anglo-Welsh league.
Gallacher's decision will lead to speculation he hopes to avoid a conflict of interest as the regions are considering leaving both competitions to play in the mooted Anglo-Welsh competition.
News of his resignation comes after the regions had called for a public inquiry as they published confidential information about their income from the tournaments they play in.
However, Gallacher's withdrawal from the tournaments' executive will not affect his day to day role with Regional Rugby Wales.
Gallacher was appointed chief executive of Regional Rugby Wales in 2009, succeeding David Moffett, the former WRU Group chief executive.