DAVOS, Switzerland (Reuters) - A Live Earth music event to demand action on climate change will take place on June 18 across seven continents, including Antarctica, former U.S. vice-president Al Gore and pop star Pharrell Williams announced on Wednesday.

Concerts will be staged in six cities -- Paris, New York, Rio de Janeiro, Beijing, Sydney and Cape Town -- in what will be the largest event of its type ever staged. The final Antarctic gig will be played by a band of scientists at a research station, Gore said.

Two billion people are expected to tune into the 24-hour event across nearly 200 television networks. Each individual concert will run for four to six hours.

Live Earth is designed to galvanize public support for climate action ahead of make-or-break United Nations’ talks in Paris in December on combating global warming.

“It is absolutely crucial that we build public will for an agreement,” Gore, winner of the Nobel Peace Prize in 2007 for his campaigning on climate change, told the World Economic Forum in Davos.

“The purpose is to have a billion voices with one message, to demand climate action now.”

Singer-producer Williams previously teamed up with Gore for a similar 24-hour Live Earth event in 2007, when performers included Snoop Dogg, Rihanna, Metallica, Genesis and Bon Jovi.

The warming of the planet is a major topic at the World Economic Forum, following inter-governmental discussions in Peru last month and ahead of the Paris talks.

Governments agreed in Lima on the building blocks of a new-style deal to combat climate change amid warnings that far tougher action will be needed to limit increases in global temperatures.

But most of the hard decisions were postponed until Paris.

Gore said the urgent case for action was highlighted by studies last week from two U.S. government agencies showing 2014 was Earth’s hottest on record, fuelling a devastating series of extreme storms.

The 10 warmest years since records began in the 19th century have all been since 1997, the U.S. data showed.

Almost 200 nations have set a rise of two degrees Celsius in average global temperature above pre-industrial times as a ceiling to limit climate change, which scientists say will bring more droughts, floods, heatwaves and rising sea levels.