The former American Vice-President was also accused of being "precious" at the London event, demanding his own VIP room and ejecting journalists, despite hopes the star-studded gathering would generate publicity for the fight against global warming.

Many of the audience at last month's Fortune Forum summit were restless as Mr Gore, who has won both a Nobel Peace Prize and an Oscar for his campaigning work this year, delivered the half-hour speech that netted him £100,000.

The glittering fundraiser was held in The Royal Courts of Justice and attracted world leaders, entrepreneurs and celebrity activists including Bob Geldof, Darryl Hannah and Jerry Hall, who was there as "a Special Ambassador of The Alliance for a New Humanity". Guests had paid between £1,000 and £50,000 to attend.