Most [pension funds] don't have the systems.. to ensure that their fine words are actually carried out

Simon McCrae, Friends of the Earth

"But many still put few or no obligations on fund managers to engage actively with the firms in which they invest to ensure ethical standards," FOE warned.

The funds with the best ethical record, FOE said, were British Telecom's pension fund, and the University Superannuation Scheme.

Funds operated by local authorities also performed well.

The worst offendors included the Pilkington, Marks & Spencer and Rover Group pension funds, which failed to adopt any ethical investment principles.

Good news, bad news

"The good news is that most pension funds in the top 100 have investment strategies that include social, environmental and ethical considerations," said Simon McCrae, investment campaigner at FOE.

"The bad news is that most don't have the systems or resources in place to ensure that their fine words are actually carried out."

FOE's review comes precisely a year after Britain introduced an amendment to the Pension Act, requiring trustees of occupational schemes to disclose the extent to which social, environmental or ethical considerations are being taken into account.

Meanwhile ethical investment is becoming more popular.

At the end of July, FTSE4good, an index of companies chosen on a variety of ethical criteria, was launched.

And FOE claimed that three-quarters of pension holders want their pension contributions to be used to help firms be socially responsible.