(CNN) With its traffic-clogged streets and polluted air it may seem like an unlikely choice, but the bustling metropolis of London is set to become the world's first National Park City.

But the UK capital won't be swapping its skyscrapers for forests. Instead, the National Park City status aims to change how people think about green spaces in urban areas.

It's the brainchild of former geography teacher Daniel Raven-Ellison. He hopes that re-imagining London as an urban national park will encourage people to conserve the natural environment and help make it greener.

"London is not just a city, it's a landscape," he said. "It's a landscape that's home not just to nearly nine million people, but there are as many trees. We share this city with 15,000 other species of wildlife and I don't think that urban life is worth any less than that life that we see in maybe those more distant places from cities."