Former City minister Lord Myners wants to replace this with a slimmed-down "plc and beyond" structure staffed by professionally-trained directors.
The former Marks & Spencer boss was appointed a director of the Co-operative Group in December but announced he is to leave following this weekend's vote.
He has said it was apparent to him from the first time he attended a board meeting that not one of its members had the ability to address the complex issues faced by a group burdened with £1.4 billion of debt.
This weekend's ballot will be decided by representatives of its independent societies and affiliated organisations - who hold 22% of the vote - and others voting on behalf of its regional membership boards making up the remaining 78%.
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The Met Police could soon be using birds of prey to help keep the skies above London clear of crime.
The PM is expected to slam the "scandalous" failure of the prisons sector today as he outlines his plans for a modern prison system.
Outbreaks of rain will continue to move eastwards across the UK this evening.