The march was part of a global protest in more than 50 countries demanding that governments meeting for Climate talks in Bali establish a strong and binding treaty to cap Co2 emissions.
The London protest was addressed by, amongst others, Tony Kearns from the executive of the CWU union. Trade union involvement in the Campaign against Climate Change is to be strengthened by a special conference in February, a flyer is avaialble here: http://www.campaigncc.org/CCCTUConf.pdf
For a BBC report of the protests see here: http://news.bbc.co.uk/1/hi/uk/7134060.stm