Directors at Morrisons are threatening to quit over chairman Sir Ken Morrison's continued failure to appoint a new chief executive, it has been reported.

A number of non-executive directors were expected to consider tendering their resignations if a new boss is not announced by the Bradford-based supermarket group's annual meeting in May, a Sunday newspaper reported yesterday.

Four of Morrisons' five non-executives have been at the company for less than ten months.

"If there isn't a chief executive by the AGM, there'll be resignations. The directors can't let themselves get tarnished over this," a source told the paper.

It is the latest round of an ongoing boardroom battle following the UK's fourth largest grocer's acquisition of Safeway in 2004. Last year, David Jones, Morrisons' senior non-executive director threatened to quit if the company failed to issue a profit warning.

It is understood that acrimony over the company's slowness to appoint a successor to Bob Stott, the incumbent chief executive, sparked a row at a board meeting on Tuesday. Tension was further heightened when Sir Ken, 74, told reporters that he hoped to still be at the company his father founded in 1899 in two to three years' time. It was thought he would stand down earlier.

It is understood Sir Ken wishes to appoint an internal candidate as Mr Stott's successor. However, directors favour an external candidate.

The issue will head the agenda at Morrisons' next board meeting on April 6.

Richard Pennycook, Morrisons' finance director, told the paper the appointment of a chief executive was a "critically important decision".

Last Thursday, Morrisons vowed to bounce back from the first annual loss in its 106-year history. Unveiling a blueprint that includes £60 million of cost savings, Morrisons said there would be no redundancy programme as it would not replace staff who chose to leave its stores.

The recovery plan was unveiled alongside losses of £312.9 million for the year to January 29 as Morrisons accounted for the cost of converting stores acquired in its £3 billion takeover of Safeway.