Sir Ken made the announcement in a statement ahead of today's AGM. The supermarket's board has invited him to remain a life president of the company following his retirement. He has been chairman since the retailer floated in 1967.
Morrisons confirmed that the search for a new chief executive to replace outgoing Bob Stott was now 'approaching the final stage', promising a 'firm announcement in the next two to three weeks'.
Heineken chief operating officer Marc Bolland, outgoing chief executive of Alliance UniChem Ian Meakins and former Tesco executive David Wild are all thought to be in the running for the top job. Bolland is believed to be favourite, but it is understood the board is struggling to make a decision.
Seymour Pierce analyst Richard Ratner said: 'Until a few days ago, we were expecting the appointment of a new chief executive to be announced at the AGM. It would appear that newspaper comments about the rift between Sir Ken and the non-executives are true.'
The group reported that like-for-like sales excluding fuel were up 3.7 per cent for the 16 weeks ending May 21.
In March, the troubled supermarket chain reported its first annual loss in its history. The£312.9 million loss was blamed on the cost of converting the final 160 Safeway stores to the Morrisons fascia. It bought rival Safeway in 2004 and a total of 220 stores have been converted so far, at a cost of£623.4 million.
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