"The original announcement in January was that Brian would hand over by 3 August and it was then up to Brian and I at which precise point we would hand over," said Martell.

"Once Brian and I were comfortable that we were in a position to hand over and we wanted to the interim results out of the way first… then [we decided to] make it clear that I'm the chief executive – so it's simply an update not a change."

Edwards will remain a director of the £439m turnover group until 3 August.

"There are some things that I would like Brian to finish off, and those are the things that he will be focusing on," added Martell.

Last week the group announced the proposed closure of its Crayford multimedia packaging plant.