More than 40 heads of state and government will attend next week's World Economic Forum (WEF) in Davos, which this year is focused on "mastering the fourth Industrial Revolution," organisers said Wednesday.

Those heading to the Swiss resort town for the high-level annual gathering also include 2,500 "leaders from business and society", the WEF said in a statement.

The headline guests include British Prime Minister David Cameron, US Vice President Joe Biden, French Prime Minister Manuel Valls and newly-elected Canadian Prime Minister Justin Trudeau.

President Mauricio Marci of Argentina, Israeli Prime Minister Benjamin Netanyahu and Alexis Tsipras, the Greek Prime Minister, are also due to attend.

North Korea, however, is no longer welcome to participate in this year's gathering following its nuclear weapon test, organisers said on Wednesday.
"After the nuclear test ... we informed them (North Korea) that participation in Davos will be subject to existing and possible forthcoming sanctions" WEF spokesman Yann Zopf said in a statement.

Describing the theme -- the Fourth Industrial Revolution -- WEF founder Klaus Shwab said it "refers to the fusion of technologies across the physical, digital and biological worlds which is creating entirely new capabilities and dramatic impacts on political, social and economic systems."

"The purpose of our meeting this year is to build a shared understanding of this change," Schwab said in a statement.

The WEF said the American delegation travelling to Davos will be largest in the history of the forum inaugurated in 1974.

Aside from Biden, Secretary of State John Kerry and Defence Secretary Ashton Carter are expected to appear, as will Attorney General Loretta Lynch who has shot to global prominence through her investigation of top FIFA executives.

This year's forum runs from January 20 to 23.