The Archbishop of Canterbury Dr Rowan Williams today blamed “human greed” for the financial crisis.

He joined Muslim leaders from around the world in calling for world leaders to work together to prevent the burden of the financial crisis from falling on “the weak and the poor.”

Dr Williams joined the Grant Mufti of Egypt Dr Ali Gomaa at Lambeth Palace in London to launch the communique from a meeting earlier this week in Cambridge, described by participants as “the most significant gathering of international Muslim leaders ever to take place in the United Kingdom.”

A Common Word, a conference of Christian and Muslim scholars, aimed at promoting better understanding between the two faiths.

The scholars examined areas on which both faiths agree, such as the need to speak out against persecution of Christians in Iraq and other minorities around the world, including Iran.

They also looked at the credit crunch from the perspective of Islam, which prohibits charging interest on lent money, and Christianity, which has changed its teaching to allow interest but still teaches against financial exploitation of the weak and vulnerable.

Asked which nation or human characteristic was most responsible for the credit crunch, Dr Williams joked: “I was going to suggest Satan.” But he added: “Clearly as religious leaders we want to say that the root of it is human greed.”

Dr Williams said he would like to see a dialogue with Islam about what constituted a just and reasonable rate of interest. “The Christian tradition has always been cautious about interest.” For many centuries, it was at one with the traditional Muslim approach, he said.

This changed around the time of the 16th century he said. The question since then was to work out “just and proper” rates of interest, rather than go for absolute prohibition.

Dr Williams said: “I would like very much to see a dialogue developing with Islam about this question of what a just, a reasonable rate of interest might look like in the light of a religious ethic but this is a work very much in its infancy, to put it mildly,” he said.

Dr Williams’ comments come after he and the Archbishop of York, Dr John Sentamu, attacked bankers and traders responsible for the financial crisis.

Dr Williams called for fresh scrutiny and regulation of the financial world and Dr Sentamu branded the traders who cashed in on falling share prices in HBOS as “bank robbers” and “asset strippers”.

Islamic banks, which operate within the restrictions set by Sharia, have been little affected by the credit crunch, according to Muslims at the conference, timed to coincide with the first anniversary of the publication of A Common Word Between Us and You, a letter from 138 Islamic scholars, clerics and intellectuals.

Addressed to Pope Benedict XVI and other Christian leaders, the letter warned that the survival of the world could be at stake if Muslims and Christians did not make peace with each other.

In their communique, the scholars said: “Meeting at a time of great turbulence in the world financial system our hearts go out to the many people throughout the world whose lives and livelihood are affected by the current crisis.

“When a crisis of this magnitude occurs, we are all tempted to think solely of ourselves and our families and ignore the treatment of minorities and the less fortunate. In this conference we are celebrating the shared values of love of God and love of neighbour, the basis of A Common Word, whilst reflecting self-critically on how often we fall short of these standards.

“We believe that the divine commandment to love our neighbour should prompt all people to act with compassion towards others, to fulfil their duty of helping to alleviate misery and hardship. It is out of an understanding of shared values that we urge world leaders and our faithful everywhere to act together to ensure that the burden of this financial crisis, and also the global environmental crisis, does not fall unevenly on the weak and the poor.”