In a letter to WRU member clubs, Gerald Davies said he made his decision not to stand for re-election to the board "with considerable sadness".
'On and off the field I hope I have demonstrated my passion and commitment to the game at all levels and I have endeavoured at all times to bring my lifetimes experience and knowledge to help contribute to the well-being of the game and all those who are involved in it throughout Wales as well as on the International stage.
I have always believed and stated that as rugby changes so its organisation must also change anD develop for the common good of all.
I do not wish to sever my ties completely with rugby and will constantly look for opportunities to encourage and support the game that is so dear to my heart.
I will watch with interest how the WRU meets the many challenges ahead."
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David and Angela Southwood, from Newport, say they plan to live in a caravan over the border after learning of the decision.