Scientists have used a gecko as inspiration to create super-strong robots that can carry over 100 times their own weight.

The nine-gram robots - built by mechanical engineers at Stanford University in California - can haul more than a kilogram up a vertical wall.

Another robot created by the scientists - nicknamed μTug - weighs just 12 grams and can drag a weight up to 2000 times heavier.

They are so successful they could be used in emergencies, in factories or on construction sites in the future.

New footage shows one robot slowly pulling an older model up a wall as it hangs on a delicate piece of string.

David Christensen, a student in the Cutkosky Lab, compared the robots' achievements to a human pulling a blue whale.

He told New Scientist: 'You can do some pretty amazing things.'

Scientists have used a gecko as inspiration to create super-strong robots, one pictured, that can carry over 100 times their own weight

Geckos have small hairs on their feet to enable them to scurry across ceilings and walls without falling off.

The robots' 'feet' are covered in tiny rubber spikes, mimicking these hairs. They were built under a microscope using tweezers.

They will be presented next month at the International Conference on Robotics and Automation in Seattle, Washington.