The leader of the British National Party and MEP is at the international summit as a representative of the European Parliament.

But he said global warming was a “hoax” designed to impose tax increases on the citizens of the world through putting up the price of energy.

He said world leaders and advocates of action on climate change such as Al Gore are “mass murderers” by supporting biofuels.

He said land for growing food is being taken to grow fuels for crops and it will cause starvation greater than the famines caused by Russian dictator Stalin during the 1930s and Chairman Mao in the 1950s.

"It is a crime against humanity which in future will be seen as an enormous man-made famine. Under Stalin 20 million people died, under Chairman Mao 30 million died. This will be the third and the greatest famine of the modern era and I regard that as a crime.”

However Mr Griffin’s own party would not give more money to the Third World.

“Britain is bankrupt. We cannot afford to go giving money to the third world,” he said.

Mr Griffin has no official role at the conference but will be speaking to delegates in an attempt to “stop the juggernaut”.

“My message is stop and think before imposing the most outrageous tax increase on people ever proposed by a group of nations on the basis of an unproven theory that is contradicted by an increasing number of scientists,” he added.

Ben Stewart of Greenpeace said Mr Griffin will bring nothing helpful to the talks.

“Mr Griffin’s conversion to the causes of the developing world is as surprising as it is cynical,” he said. “In reality the environmental and development groups he has been disparaging have been in the forefront of concerns about biofuels. Griffin’s claims that climate change is a hoax is one of many curious things going on between his ears.”