Embattled Co-operative Group was left in fresh turmoil late on Wednesday when former City minister Lord Myners quit the board over his controversial plans to "reform" the business.

It was understood that while he had tendered his resignation as an independent director, he would carry on with his review.

According to a report in The Guardian, his review is unlikely to be accepted by the regional boards and independent societies which run the organisation.

On Wednesday the Co-op's largest independent society, the Midcounties Co-operative, was accused of making a "meaningless" political statement by voting against reform plans.

But Lord Myners said the vote looked "premature" given that his report would not be complete until the end of this month.

Reform plans include a move to abolish the wider group's 21-member board, splitting it into two with a plc-style panel responsible for commercial decisions and representatives from its traditional membership sitting on a separate body.