Collier-Keywood’s departure comes at a time of chaos and uncertainty for the professional game in Wales.
The WRU is pushing on with highly controversial plans to cut the number of men’s teams from four – Scarlets, Ospreys, Cardiff, Dragons – to three by June 2027.
That proposal has been met with criticism, protests and legal action from both Scarlets and Swansea Council.
Collier-Keywood has been forced to appear before politicians both in Wales and Westminster in recent months and has come under major criticism for his handling of the plans.
“Over the course of the last few years, the new board has made key decisions unanimously despite the very difficult choices we have had to face,” he said.
“I am fully committed to serving out the remainder of my term, subject of course, to the outcome of the EGM.
“The people I have had the pleasure of working with in the WRU and outside, and the importance of and passion for rugby in Wales, have been a source of continued inspiration to me in carrying out this role.
“I am pleased to leave with two Welsh head coaches in place with Steve Tandy and Sean Lynn and I am looking forward to watching from the terraces as our teams go from strength to strength.”