The Co-operative Group has "acknowledged its governance is not up to scratch", Lord Myners said following members unanimously voting for reforms.
Lord Myners said: "I'm thrilled with the outcome today...there has been a fundamental change in position".
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Judges at the European Court of Human Rights have refused to intervene in the life-support treatment fight.
Supporters of Mark Meechan, including former English Defence League leader Tommy Robinson, were at court for the hearing.
It was Tom's second marathon in two weeks run in memory of his father, Martin Campbell.