Lord Haskins, the former Northern Foods chairman, has told The Grocer he believes the cause of his former employer's problems can be traced back to its poor handling of supermarkets.

Speaking in the wake of news that Northern's chief executive Pat O'Driscoll is to step down, Lord Haskins said the company had failed to keep its biggest customers on side.

"It hasn't got the relationship right with the supermarkets, and if you haven't got that right then you're in trouble. Northern has the tendency to criticise its customers, and it's a bad idea. You do have to stand up to them but it's not wise to openly criticise them."

Lord Haskins conceded O'Driscoll had inherited problems when she took over in March 2004 - but still bore some culpability. "I'm not really surprised that she's leaving," he said. "I feel sorry for her but that's the way it goes. O'Driscoll inherited a difficult situation but I don't think she did much to mitigate it. When I left six years ago the profit was £100m, now it's £40m." O'Driscoll, 47, announced on Thursday that she was leaving. She will be replaced from 5 February by Stefan Barden, executive director responsible for the chilled and bakery divisions.

O'Driscoll led Northern through restructuring in a bid to increase the company's focus on branded goods. This culminated in the sale of 40% of its operations to private equity group Vision Capital for £203m earlier this year. "The business has been through three years of change, which I came in to lead," she said in an interview with The Grocer this week. "Having completed that I spoke to the board about what the business needed and we agreed it was the right time to make a change of leadership."

She will stay on for three months in the role of "handover executive".

One industry insider commented: "O'Driscoll's time at Northern Foods has been an unmitigated disaster. She has spent a fortune restructuring the business, but destroyed shareholder value.

"And the jury is out on Stefan Barden as he has little experience running a mainly chilled, own-label business."