The march was organised by an unprecedented alliance of more than 150 organisations, including The Salvation Army, World Vision, Oxfam and Friends of the Earth.
Prior to the march, Christians gathered for an ecumenical service at Methodist Central Hall in Westminster joined by the Bishop of London, Dr Richard Chartres.
“It is an interconnected world,” he told the congregation. “If we take more than our fair share of the Earth’s resources and if we contribute to climate change then it is going to be the most vulnerable and poorest people in the world who suffer first.”
Dr Chartres added that future generations would pay the price if leaders failed to adequately respond to the current “global emergency”.
“We’ve mortgaged some of our children’s tomorrow to fund our today,” he said.
Dr Chartres said world leaders needed to agree adaptation funds for poorer countries and cuts in carbon emissions when they meet in Copenhagen for a major summit on climate change in December.
Also speaking at the service was Joel Edwards, the head of Micah Challenge International. He told Christians to be persistent in their calls for justice.
“For the first time in human history we have reached the place where we are potentially irreversibly damaging our environment,” he said.
“What we are calling upon you and ourselves to do is simply to remind our world of an agreement we made to be hospitable and just to everybody on our planet – God expects no less,” he said.
Father Joe Komakoma, Secretary General of the Zambia Episcopal Conference, said G20 leaders could not afford to go back to business as usual. He spoke of how developing countries are struggling to cope with the knock-on effect of the economic crisis.
“Developing and poor countries like Zambia where I come from have been hit hardest by this crisis although the problem has originated from the rich countries,” he said.
“Whereas rich countries can afford to come up with stimulus packages worth billions of pounds, poor countries have limited opportunities to cope with the current crisis.
“This is because we from the poor countries are still struggling with providing the basic needs for our people such as food, clean water, sanitation and decent housing.”
Father Komakoma called on governments and international institutions to agree just economic and social policies that promote the welfare of the world’s poorest people, as well as give poor countries a place at the table of the G20 and other international forums.
He added: “The situation of entrenched global poverty and injustice now made worse by the current economic crisis is not acceptable as it goes against God’s vision for humanity. It violates the God-given dignity of human being.”
