At least 12 cheeky squirrel monkeys escaped London Zoo by scaling trees and leaping into Regent's Park.

The Sun reports zoo keepers could only watch as the animals swung back and forth between the park and the zoo.

A statement by the zoo says, "The squirrel monkeys at London Zoo have breached the perimeter of their enclosure. The monkeys are closely supervised at all times and are currently being monitored within Regent's Park.

"The squirrel monkeys have managed to gain access to some of the taller trees in their enclosure and from there, have leapt into the higher branches of a tree in Regent's Park. We have identified where the breach is occurring and currently have tree surgeons working in the enclosure to rectify this."

The escape of the monkeys was their latest escapade after developing a knack for stealing mobile phones from unsuspecting visitors.

The statements adds, "Squirrel monkeys are not a dangerous animal, their enclosure is a walk-through exhibit, and they pose no threat to the public."