Profiling the award-winning environmental campaign work of Archbishop Bartholomew of Constantinople, spiritual leader of 300 million Orthodox Christians, Riazat Butt asks if religion can help prevent eco-catastrophe (The pope of hope, June 18). After all, as the archbishop told Butt: "Religious people were indifferent, or even hostile, to science. Scientists and ecologists could see little relationship between their world and the world of faith."

At a global environment conference in London last year, my professional institution, the Chartered Institution of Water and Environmental Management, brought together representatives of all the major faiths. There was one matter on which they all agreed: the need to collaborate for action on the environment, and especially on climate change. The leadership of Archbishop Bartholomew was seen as a beacon.

But faith groups have been silent for too long on this crisis, and should do far more to remind us of our moral duty to restore and protect the fragile ecological balance of the planet. As the archbishop said: "We are all culpable. Each one of us has a smaller or greater contribution to the deliberate degradation of nature."

Butt, in reporting the environmentalism of some religious leaders, suggests that an ecological coalition of faiths is possible: "There is hardly a religious leader in the world now who is not preoccupied by the problems of pollution and climate change." And it's true. In the last year or so we have seen faith leaders including the Dalai Lama, the Bishop of Liverpool and Pope Benedict step down from the pulpit and speak directly on environmental issues. This is good news and "God-bothering" of the sort we need for the 21st century.

What the faith groups can offer is a framework - ethical, spiritual, imaginative and intellectual - for the pursuit of all the good that relates to human destiny. Fazlun Khalid, director of the Islamic Foundation for Ecology and Environmental Sciences, has urged faiths to civilise and change behaviour for a fairer, sustainable world. But they must engage with people and evangelise first - heeding Bartholomew's big idea for an economic model that is about replenishment, compassion and nurturing. In other words: it's creation, stupid!

In the meantime, as Archbishop Bartholomew warns, cohorts of secularists continue to pursue greedy and harmful lifestyles believing that techno-fix solutions alone will be our salvation. The truth is that blind faith in the ability of technology to sustain a growing global population - hard-wired to materialism - that has already breached environmental limits is bonkers. Faith group leaders must be more vociferous in challenging this - they have unique access to governments and institutions. They must exercise that influence by holding them to account.

Religion can help prevent eco-catastrophe. And, as Butt's report argues: "Religious leaders are in a better position to make an impact on their congregations than politicians or celebrities." They have a huge audience and legitimacy over the issue. What are they waiting for?

· Nick Reeves is executive director of the Chartered Institution of Water and Environmental Management nick@ciwem.org