London police have slapped the cuffs on a would-be thief who made off with a piece of Banksy street art as witnesses watched in open-mouth astonishment.

The picture depicting a stop sign decorated with a trio of military drones had been on display less than an hour after the elusive street artist posted a photo of the work on his Instagram page on Friday.

Video showed a man with bolt cutters using a bicycle as a ladder to remove the work from a sign post on a street corner in the Peckham area of south London while another man steadied the bike.

The man who cut the sign free then ran off with it in his hand.

A voice on a video of the incident could be heard saying, “it makes me so annoyed,” as the man ran away.

‘What are you doing?’

A witness who only wanted to be called Alex told the PA news agency that the small crowd that showed up to view the work stood passively as the scene unfolded.

“We said, ‘What are you doing?’ But no one really knew what to do, we sort of just watched it happen,” Alex said.

“We were all a bit bemused; there was some honking of car horns.”

It was initially not clear if the artwork’s removal was part of a stunt.

Jasmine Ali, deputy leader of the local borough council, called for the piece to be returned.

“It should not have been removed and we’d like it back so everyone in the community can enjoy Banksy’s brilliant work,” Ali said.

The stop sign was replaced.

Banksy’s thought-provoking and satirical art often takes aim at war.

Many of his followers on Instagram interpreted the work as calling for a ceasefire in the Gaza Strip.

-with AAP