A global environmental initiative, Earth Hour, will invite people around the world to switch off their lights for one hour on March 26, according to a Friday release from the World Wildlife Fund.
The event which aims to show "an unambiguous commitment to the planet" will start at 8.30 p.m. with the expected participation of hundreds of millions of people, it said.
Some of the world's most recognized landmarks --the Forbidden City, Eiffel Tower, and Buckingham Palace-- have pledged to switch off their lights.
According to the press release, this year's campaign will also ask participants to share stories about actions that benefit the planet on earthhour.org which will come online next month.
Earth Hour began in Sydney three years ago, when two million people switched off their lights.
The event has become the largest voluntary action ever recorded and involves participants in 128 countries throughout the world.
Vietnam joined the initiative in 2009 and 2010 with the participation of millions of individuals, organizations and businesses.