Women must be given control over their bodies if mankind is to survive as a species, David Attenborough has said.
The broadcaster and naturalist said that the world's booming population – predicted to hit 11 billion by 2100 – will lead to our extinction unless something is done to tackle the problem.
Speaking to the Independent, he said that if humans do not work to redress the balance, the natural world will do something about it and "we will starve".
"It's desperately difficult, the dangers are apparent to anybody," he said. "We can't go on increasing at the rate human beings are increasing forever because the Earth is finite and you can't put infinity into something that is finite."
Attenborough said that giving women political control over their bodies is the best solution to curb the ever increasing population.
"The only straw of comfort or of hope, and even that is pretty fragile, is that wherever women are given political control of their bodies, where they have the vote, education, appropriate medical facilities and they can read and have rights and so on, the birth rate falls, there's no exceptions to that.
"There are still quite a lot of parts of the world where those things don't apply, so those of us who live in the parts where they do apply ought to help the others to have that possibility."
The 88-year-old warned, however, that this still will not be enough, but added: "Just because you don't know the answer to the problem doesn't mean you shouldn't say there is one."
Attenborough's latest documentary Conquest of the Skies is on New Year's Day at 7pm on Sky 3D and Sky 1.