Post-Catatonic

with a shopping trolley has been hung on the walls of the British Museum.

The rock was put there by art prankster Banksy, who has previously put works in galleries in London and New York.

A British Museum spokeswoman said they were “seeing the lighter side of it”. She said it went unnoticed for one or two days but Banksy said three days.

Banksy also hung a sign saying the cave art showed “early man venturing towards the out-of-town hunting grounds”.

It read: “This finely preserved example of primitive art dates from the Post-Catatonic era.

“The artist responsible is known to have created a substantial body of work across South East of England under the moniker Banksymus Maximus but little else is known about him.

“Most art of this type has unfortunately not survived. The majority is destroyed by zealous municipal officials who fail to recognise the artistic merit and historical value of daubing on walls.”