A POSTER telling staff at Sainsbury's to encourage customers to spend more has attracted mockery on social media after it mistakenly appeared in a shop window instead of the staff room.

The poster advertising the "50 pence challenge" was posted in the window of the Romford Road branch of Sainsbury's in Stratford, east London and read: "Let's encourage every customer to spend an additional 50p during each shopping trip between now and the year end."

Television freelancer Chris Dodd spotted the poster and posted a picture of it on Twitter with the caption: "Not sure this is supposed to be in your window..."

Others were quick to ridicule the poster. Some had suggestions for how Sainsbury's could secure the extra spending, such as "Double swipe a 50p item at the checkout maybe?", and "When customers are not looking, just stuff a few extra items into their basket".