Volkswagen, Air France and Mobil are among a number of corporate brands under fire from climate change activists who have targeted them in a series of damning ads installed throughout Paris to coincide with the beginning of the COP21 climate change talks.

The ads are part of the Brandalism campaign, an anti-advertising movement which takes over advertising spaces in cities throughout Europe to challenge authority and criticise perceived wrongdoing. The artworks were placed in advertising spaces owned by JCDecaux, one of the talks' sponsors.

Prominent corporate sponsors of the UN summit on climate change such as Volkswagen, Air France and oil companies Mobil and Total have been castigated in some of the group’s 600 unauthorised artworks which say they are “part of the problem”.

The ads chastise the brands for their public commitments to tackling climate change, accusing them of lying and greed.

In June this year Air France signed a statement confirming its commitment to reduce its environmental footprint and increase the use of sustainable alternative fuels. The Brandalism campaign however accused the company of bribing politicians to ensure its profits aren’t affected by any emission laws.

Volkswagen was unsurprisingly targeted in the campaign following the emissions scandal in which the car manufacturer was caught installing software in 11 million cars that cheated emissions tests, making the vehicles appear greener than they actually were.

Mobil, which merged with Exxon in 1999, was also denounced after it was caught giving $2.3m to members of Congress and a corporate lobbying group that block efforts to fight climate change.

In a statement, the activists’ said that the aim was to "highlight the links between advertising, consumerism, fossil fuel dependency and climate change".

The Conference of Parties (COP21) talks, which commenced today (30 November) and are due to run through until 11 December, bring together leaders from 147 nations in the hope that a global agreement can be met on how best to tackle climate change and reduce carbon emissions.

World leaders were also part of the campaign.

David Cameron was portrayed wearing Formula 1 gear.