A major UN report on climate change has been watered down as a result of influence from government officials from countries opposed to taking radical action, according to WWF.

It says “vital facts” have been cut from the report’s summary, including a warning of more destructive hurricanes, the warming of the upper Pacific Ocean and the loss of glaciers in the European Alps.

“There is a contrast between the immense wealth of the IPCC’s work and the politically inspired trimming back in this report,” says Hans Verolme, Director of WWF’s Global Climate Change Programme. The report, which will be released on Saturday, will say that almost a third of the world’s species will face extinction if greenhouse gas emissions continue to rise.

A draft copy of the report by the UN’s Intergovernmental Panel on Climate Change (IPCC) also warns that if temperatures rise by more than two degrees – now expected before 2050 – 20 per cent of the world’s population will face a great risk of drought.