In her annual Commonwealth Day message, she will say that the impact of climate change is often worst for those countries who pollute the least.

And she will suggest that the developed world should work with communities that are most affected to bring about lasting change.

"Happily, this approach has always been a strength of the Commonwealth, and awareness of environmental issues is now widespread, with a determination that future generations should enjoy clean air, sufficient fresh water and energy without risking damage to the planet," the Queen will say.

In her message for 2008, the Queen will refer to last year's meeting of Commonwealth heads of government on the edge of Lake Victoria in Uganda where they agreed to an action plan for tackling climate change.

The Queen will say: "It was an appropriate place to do so: from there, the waters of the River Nile begin a three-month journey to the Mediterranean.

"The Nile, throughout history, has served humankind in many ways. But for all its impressive size and importance, this river is a fragile eco-system; and its vulnerability grows with the number of people dependent upon it, so that a single incident of pollution upstream may affect the lives of countless numbers downstream.

"The example of the Nile illustrates many of the challenges facing the global environment as a whole which cannot alone sustain our lives as once it did. The competition for fresh water by a growing population is itself becoming a source of potential conflict."

She will remind the Commonwealth that attitudes to the environment in their own country may have consequences for people on every continent and for every ocean and sea.

The Queen will praise young people's energy and awareness in confronting climate change. She will ask for them to be supported and for the Commonwealth, governments, businesses, communities and individuals to "match words and good intentions with deeds".