Mr President and colleagues. We know the problems. A child in Africa dies every three seconds from famine, disease or conflict. We know that if climate change is not stopped, all parts of the world will suffer. Some will even be destroyed, and we know the solution - sustainable development. So the issue for this summit is the political will.
We know one other thing. The key characteristic of today's world is its inter-dependence. Your problem becomes my problem. One country's war becomes another country's asylum seekers. One country's pollution becomes another country's floods.
We have begun to act.
A decade from Rio, for all the sneering about summits, those who took part then can point to the real progress there has been - millions more children educated, millions more with safe drinking water, millions lifted out of poverty.
Rio of course did not deliver everything, neither will Johannesburg, no summit can, but this summit can and will make our world change for the better.
Today I re-state Britain's commitment to play our full part in this. Development for us is a priority. Africa for me is a passion, proud of our leadership on debt relief, we know there is more to do; proud of the extra resources we are giving to aid and development, we want to give more in the future and we will, proud that we will meet, indeed exceed, our Kyoto targets, we know we must do more.
There are certain specific agreements this summit can deliver, on poverty, on education, on fish stocks, on chemicals, on sanitation, on biodiversity.
But beyond that this summit has to set a clear direction for the future for our world.
We must open up our world trade and that must include the developed world opening up its markets to the products of the developing world, especially for agriculture.
It then means sustainable and fair development, globalisation with justice to ensure that the benefits are spread to every nation in the world.
It means driving through the partnership with Africa. I can tell you that Britain will raise by 2006 its commitment to development aid to Africa to ??1 billion a year and its overall levels of assistance to all countries by 50%. This is not charity, it is an investment in our collective future. Of course poverty damages the poor most, but it also deprives the whole of the world of the benefits of the industry and the talent of poorer nations and their people.
It also means changing the way we consume resources, particularly energy, and it means the world - the whole world - facing up to the challenge of climate change.
Kyoto is right and it should be ratified by all of us, but Kyoto only slows the present rate of damage, to reverse it we need to reduce dramatically the level of pollution, and let us at least start to set that direction.
Mr President, none of this is easy, the short term clashes with the long term, there are painful decisions, vested interests, legitimate anxieties. But the facts remain, the consequences of inaction on these issues are not unknown, they are calculable. Poverty and environmental degradation, if unchecked, spell catastrophe for our world, that is clear.
My politics, like the politics of many of you, is founded on the belief that we are all of equal worth.
Yesterday in some of the poorest parts of Mozambique, I saw children every bit as bright as children in affluent Britain, full of potential, despite all the challenges of hope, but their life chances are stunted by poor health, poor housing, poor education, poor sanitation.
Those children need not, and must not, face the challenge alone. If Africa is a scar on the conscience of our world, the world has a duty to heal it, heal it we can and we must.
So the decisions taken here will bear directly on the lives of those children. Let us be sure that we make the right decisions. We know the problems. We know the solutions. Let us together find the political will to deliver them.