The Wales Online report is here. We understand that he wants to spend more time with his family and on his farm.
Frank Little writes: I hope this resigning from the cockpit of daily politics does not mean that Mick is lost to party activity altogether. His contributions to Liberal Democrat conferences are virtually guaranteed to liven proceedings. Although his enthusiasm for wind power generation goes farther than I would, there is no doubting that he has given a major boost to green politics in Wales from a time when it was not as main-stream as it is now.