PARIS, March 26: Hundreds of landmark buildings and millions of ordinary homes switched off their lights on Saturday night as the annual `Earth Hour` moved around the globe in what was dubbed the world`s largest voluntary action for the environment.

In Pakistan, a special ceremony was held at the National Assembly building in Islamabad to mark the occasion.

As the clock struck 8.30pm, the lights of the building were switched off and candles were lit by parliamentarians, students, officials of the ministry of environment and other civil society members.

The Earth Hour was observed by all federal and provincial government secretariats and departments in the country.

Australia`s Opera House was the first of many global landmarks to go dark as the event got under way, as hundreds of millions of people prepared to follow suit to enhance awareness of energy use and climate change.

Others waiting for their turn included Beijing`s “Bird`s Nest” stadium that hosted the 2008 Olympics, the Eiffel Tower in Paris, the London Eye Ferris wheel, Times Square in New York and Brazil`s Christ the Redeemer statue.

Most were switching off their floodlighting, advertising signs and other illuminations for an hour from 8.30 pm local time.—Agencies