A humorous spate of ads mocking corporate sponsorship of the Conference of Parties (COP) 21 climate talks in Paris has sprung up in hundreds of bus shelters across the French capital.

The joke ads are targeting corporate backers of the Paris talks including global heavyweights like Dow Chemicals and BP, as well as heads of state such as French president François Hollande, British PM David Cameron, President Barack Obama, German chancellor Angela Merkel and Japan's Shinzo Abe have also been lampooned.

The British 'Brandalism' art project joined forces with Parisians to insert unauthorized artworks across the city that aim to highlight the links between advertising, consumerism, fossil fuel dependency and climate change. The ads went up after French authorities declared a state of emergency following the Nov. 13 Paris terror attacks, banning large-scale public gatherings and protests.