I'm writing this now to make sure our children have a chance of growing up in a world worth living in.
Today there's still time to save nature.
If we act now, our children may yet be able to share their world with sparrows and polar bears, eagles and tigers. There's still a chance that they'll inherit a world where the engines of life - the air, seas, rivers and forests - are healthy. Where bluebell woods and rainforests won't be lost forever.
Yes, I accept that recovery from recession has meant spending billions of pounds - one way or another future generations will have to pay for this. The least we can do is to use this money to create a future they'll thank us for.
I want governments to invest in a healthy economy and a healthy environment. As well as protecting jobs, I want them to tackle climate change and to protect our seas, countryside and wildlife.
I'm signing this letter to show that I care deeply about nature and the world we are creating for our children. In years to come I hope they'll be able to see that their world is a richer one because of the action we took today.
I'm hoping that many thousands of people will join me in signing it.
Together we can be a powerful voice for nature.
Yours in hope.