David Cameron is due to launch a new global prize for inventors or scientists who can identify and solve the biggest problem of our time.
The Government will commit £1 million to a fund for the grand prize, with hopes that it will inspire innovators to create something to change the world.
Downing Street hopes the competition will capture the public imagination, and could result in the creation of revolutionary technologies such as new forms of low-carbon travel or advances in medical science to create replacement limbs.
The Prime Minister will announce the prize fund at the G8 Innovation Conference ahead of next week's meeting of leaders from the world's richest countries.
A Downing Street source said: "We want people to think big. What does the world need and how can we achieve that? We are looking for the next penicillin, aeroplane or worldwide web. Can we grow limbs or create universal low-carbon travel? Something that is going to really revolutionise what we do and how we live our lives - sending us sprinting ahead in the global race."
The initiative is inspired by the Longitude Prize set by the British government in 1714, which promised £20,000 to the person who mastered the challenge of calculating longitude at sea to help maritime navigation.
Astronomer Royal Lord Rees will chair the new Longitude Committee, with £500,000 pledged by innovation organisation Nesta to support its work.
The Prime Minister will also announce £50 million of funding, from within the UK's aid budget, for ideas to make a difference in the developing world.
At the G8 Innovation Conference in east London, Mr Cameron will say: "More than any time in history, our world is being shaped by innovation, new ideas, new technologies and new companies. This is the story of the global economy.
"Countries around the world have got to get this. Jobs and growth depend on it. We've all got to open up our economies to innovation, we've got to nurture new ideas, we've got to bend over backwards to attract the best and the brightest. A global race is under way and it is waiting for absolutely no one."