Prototypes could be on the front line by the end of the year, scuttling into potential danger areas such as booby-trapped buildings or enemy hideouts to relay images back to troops safely positioned nearby.

Soldiers will carry the robots into combat and use a small tracked vehicle to transport them closer to their targets.

Then they would swarm into the building and relay images back to the soldiers' hand-held or wrist-mounted computers, warning them of any threats inside.

BAE Systems has just signed a 19million contract to develop the robots for the US Army.

Researchers hope they will eventually create machines that can fly like a butterfly

Plans for a creature that can crawl like a spider are said to be well developed, and researchers eventually hope to be able to create creatures that can slither like a snake or fly like a dragonfly.

While some of the creatures will be fitted with small cameras, others will be equipped with sensors that will be able to detect the presence of chemical, biological or radioactive weapons.

A computer-generated video from BAE Systems shows the tiny invaders being released by a soldier, before scouting out a suspect building, which is finally blown up by ground forces.

BAE Systems scientists from the UK and America plan an army of the electronic bugs, and have ambitions to equip every front-line soldier with them.

Programme manager Steve Scalera was inspired by the way creatures use their senses to detect danger.