Last week Tesco chief executive Philip Clarke faced an unusual question at the grocer’s AGM between the more staid queries about doubts over pay and write-downs.

A shareholder asked why Tesco is stocking Nigerian Guinness instead of the more well-known Dublin black stuff.

Clarke countered that the grocer stocks both, because the African product is sweeter and popular with Afro-Caribbean shoppers.

Perhaps Clarke will celebrate St Patrick’s Day next year in style with a pint of the local stout in Lagos.