Hundreds of campaign groups on Thursday condemned the appointment of an oil boss to lead UN climate talks in the United Arab Emirates, saying it threatened the meeting's "legitimacy".
The UAE named Sultan Al-Jaber, chief executive of the Abu Dhabi National Oil Company (ADNOC), to head the crucial COP28 climate meeting in November, sparking an outcry from activists.
He is the first CEO to take the role at the UN summit.
NGOs and civil society organisations from around the world said in an open letter Thursday the "decision threatens the legitimacy and efficacy of COP28.
"This is no cause for celebration," it added in the letter to UN chief Antonio Guterres and Simon Stiell, executive secretary of the United Nations Framework Convention on Climate Change (UNFCCC), under which all climate negotiations are held.
"If we have any hope of addressing the climate crisis, every COP must be free from the polluting influence of the fossil fuel industry," the letter added.
Experts have repeatedly warned that the world is not on track to limit warming by the 1.5 degrees Celsius set out in the Paris agreement. If that target is to be met, they say, no new fossil fuel projects can come online.
The UAE, a leading crude producer and one of the world's biggest polluters per capita, argues that oil remains indispensable to the global economy.
It is pushing the merits of carbon capture - removing carbon dioxide, the main greenhouse gas, as fuel is burned or from the air.
"The UAE's track record demonstrates it is not serious about phasing out fossil fuel use and keeping global temperature rise to below 1.5 degrees Celsius," the letter Thursday said.
"It is central to causing the climate crisis, not solving it".
The signatories called on the UNFCCC not to allow "big polluters" to influence climate policymaking or sponsor climate talks.
They said "world governments continue to treat the UNFCCC as an industry PR stunt and corporate trade show", despite increasing climate impacts.
The UAE had one of the largest contingents of oil and gas lobbyists at the last COP held in Egypt in November.
That meeting concluded with a landmark agreement to create a "loss and damage" fund to cover the costs that developing countries face from climate-linked natural disasters and slower impacts like sea level rise.
But observers left disappointed that little progress had been made on reducing the planet-heating emissions from fossil fuels.
When Al-Jaber was announced as the head of the next COP meeting, US climate envoy John Kerry called the UAE "a crucial partner" in the climate crisis.
"The path ahead will not be easy, but I am optimistic at the outset of 2023 that we can collectively rise to meet the challenge of the climate crisis," Kerry said at the time.