The key is a type of microscopic Velcro that clings to smooth surfaces, such as concrete or glass, but is still easy to detach.

Insects, spiders and gecko lizards all used the same principle to scuttle effortlessly up walls.

They have tiny hairs on their feet which set up weak attractions called Van der Waals forces between molecules that are very close together.

Italian scientists have calculated how sufficient stickiness could be generated in the same way to support a fully grown human being’s bodyweight.

They believe microscopic hollow structures called carbon nanotubes could theoretically be used to make the idea work.

Professor Nicola Pugno, of the Polytechnic of Turin, who led the research published today in the Journal of Physics, said: "There are many interesting applications for our theory, from space exploration and defence, to designing gloves and shoes for window cleaners of big skyscrapers.

"Now that we are this step closer, it may not be long before we are seeing people climbing up the Empire State Building with nothing but sticky shoes and gloves to support them."