On Saturday 28 March 2009 at 8.30pm, people, businesses and iconic buildings around the world will switch off their lights for an hour – WWF’s Earth Hour.

Let’s help London take part. By switching off you can do your bit for climate change and make a real difference.

London Mayor Boris Johnson has suggested he’ll be sitting in a state of "tranquil calm" in his darkened office during WWF’s Earth Hour. What will you do?

For more ideas check out the WWF website: http://earthhour.wwf.org.uk/what_we_do/