The PRI scheme is designed to encourage sustainable investing by incorporating environmental, social and governance issues into investment decision-making and ownership practices.

To date, there have been 988 signatories, 126 of which are from the UK.

Man chief executive Peter Clarke, said: “This step is a signal of Man’s continued commitment to responsible investing. As a leading alternative asset manager, we hope that by signing up to the UN PRI we will encourage others in our industry to follow our lead.”

Senior managing director of GLG, a Man Group company said: “Investing sustainably enhances long-term value and reduced risk which is clearly good for all concerned: investment manager, their clients, society, and the environment.”

Jason Mitchell, portfolio manager at the GLG Global Sustainability Equity Fund said: “Man’s support recognises our commitment to help advance the UN PRI agenda, and attests to the positive effects that normative, international frameworks like the PRI bring to the investment community. It also marks the next step in a process that began with our legacy in environmental funds, expanded into broader global sustainability themes and is driving our current work developing the application of sustainability across alternative strategies.”

As of 31 December 2011, LSE-listed Man managed $58.4bn.

The PRI can be traced back to a 2005 invitation by the UN secretary general who invited a group of the world's largest institutional investors to join a process in developing the scheme. As of October 2011 it had assets under management of approximately $30trn.