The United Nations will participate in Earth Hour on Saturday by turning off all lighting for three hours at its headquarters in New York. "In order to demonstrate the UN's commitment to support action on climate change, and in the lead-up to the Climate Summit, this year the UN is going the extra mile and turning off all non- essential lights within the UN complex in New York for three hours from 7:00 p.m. to 10:00 p.m.," according to a message on the UN website. "The offices in Geneva, Switzerland and many other UN locations worldwide will also participate," it added. This is the fifth year that the United Nations will join scores of other landmark buildings around the world in the Earth Hour event. The 2014 edition of Earth Hour will take place on Saturday, March 29, and everyone around the world is invited to switch off their lights for one hour from 8:30 to 9:30 p.m., local time worldwide. Earth Hour, a symbolic global initiative organized by the World Wildlife Fund (WWF), started as a lights-off event in Sydney, Australia in 2007. Since then it has grown to engage over 150 countries and hundreds of millions of people. "WWF has been raising international awareness about climate change and renewable energy with the Earth Hour campaign," UN Secretary-General Ban Ki-moon said on Friday in a video message for the opening of the WWF office in Seoul, South Korea. "I look forward to joining you on March 29 as we switch off our lights for one hour -- and switch on to a cleaner, greener future, " Ban said. The date of the Earth Hour event traditionally coincides with the Spring and Autumn equinoxes in the northern and southern hemispheres respectively, which allows for near coincidental sunset times in both hemispheres, thereby ensuring the greatest visual impact for a global "lights out" event.