The United Arab Emirates’ state oil company has been able to read emails to and from the Cop28 climate summit office and was consulted on how to respond to a media inquiry, the Guardian can reveal. The UAE is hosting the UN climate summit in November and the president of Cop28 is Sultan Al Jaber, who is also chief executive of the Abu Dhabi National Oil Company (Adnoc). The revelations have been called “explosive” and a “scandal” by lawmakers. The Cop28 office had claimed its email system was “standalone” and “separate” from that of Adnoc. But expert technical analysis showed the office shared email servers with Adnoc. After the Guardian’s inquiries, the Cop28 office switched to a different server on Monday. Al Jaber’s dual role has attracted strong criticism, including from the former UN climate chief Christiana Figueres, who called his approach “dangerous”. Replies to a Guardian email to the Cop28 office requesting reaction to these comments, which did not mention Adnoc, contained the text “Adnoc classification: internal”. The French MEP Manon Aubry, said: “This is an absolute scandal. An oil and gas company has found its way to the core of the organisation in charge of coordinating the phasing out of oil and gas. It is like having a tobacco multinational overseeing the internal work of the World Health Organization.” Aubry, who co-led a recent letter to the UN from 133 US and EU politicians calling for the removal of Al Jaber, said: “The Cop28 office has lost all credibility. If we care more about preventing a climate disaster than protecting the profits and influence of fossil fuel companies, we need to react now.” Pascoe Sabido, at Corporate Europe Observatory and co-coordinator of the Kick Big Polluters Out coalition of more than 450 organisations, said the revelations were outrageous and that Al Jaber’s appointment had been “a huge blow to the credibility” of the UN’s climate body, the UNFCCC. “It’s completely inappropriate that an oil corporation was consulted and it exposes just how influential it has been in shaping what gets presented to the outside world,” Sabido said. “Until world governments accept that fossil fuels need to be left in the ground and their lobbyists are no longer allowed to write the rules of climate action, this will keep happening.” A senior international climate policy expert, who requested anonymity, said: “The UAE have been advised by many actors since it became clear they would host Cop28 that they should separate out the presidency from Adnoc. They also were advised that Sultan Al Jaber should step down from his roles at Adnoc, even if temporarily. Despite a six-month listening tour, they do not seem to have picked up on this advice.” The Guardian revealed in April that the UAE had the third biggest net zero-busting plans for oil and gas expansion in the world. The International Energy Agency, the Intergovernmental Panel on Climate Change and a large consensus of scientists are clear that new oil and gasfields are incompatible with the 1.5C target of the Paris agreement. In addition to being the head of Adnoc, Al Jaber chairs Masdar, a renewable energy company, and was the UAE climate envoy from 2010 to 2016 – he was reappointed to the post in 2020. He received support from senior figures shortly after his appointment as Cop28 president in January, including from the US climate envoy John Kerry and EU climate chief Frans Timmermans. The Guardian discovered the links between the UAE’s Cop28 office and Adnoc after requesting a response to Figueres’s criticisms in mid-May. When asked why the email replies contained the text “Adnoc classification: internal”, the Cop28 office said it had “sought input from several subject matter experts regarding emissions, including Adnoc” and that the internal classification mark had become part of the email chain as a result. The Guardian also asked if the Cop28 office shared an IT system with Adnoc. Politico reported in January that the UNFCCC had sent a “series of questions inquiring whether the presidency will be independent of the oil company … including whether there is a firewall between the two institutions; whether Adnoc has access to Cop28 meetings and strategic documents; if [Cop28] staff are relying on the oil giant’s IT systems”. The Cop28 office replied to the Guardian on 23 May, with a spokesperson stating: “Cop28 can confirm that Cop28 content (including emails) are held in separate servers, housed in the Cop28 offices, on a standalone, firewall-protected network, supported by a separate Cop28 IT team.” However, expert technical analysis for the Guardian of the headers of emails from the Cop28 office and from an earlier email chain between the Guardian and the oil company revealed that Adnoc servers were involved in both sending and receiving emails from the Cop28 office. “The [Cop28] server handed everything off to the oil company’s server to send the email out,” said Dr Richard Clayton, at the Computer Laboratory at the University of Cambridge, UK, and an expert in traceability. “The oil company was able to look at all of the email which they were sending out.” Prof Alan Woodward, a computer security expert at the University of Surrey, UK, added: “Both the [Cop28] and Adnoc emails use the same primary email external service. Their MX record – where their email is sent to – was the same Proofpoint server.” In response to the finding that Adnoc servers were involved in Cop28 office communications, the Cop28 spokesperson said on 2 June: “For the past few months, Cop28 has been using a dedicated Microsoft 365 tenant and email service. We have been migrating our data from the previous host to our own setup and we expect that this process will be complete by 5 June.” The MEP Bas Eickhout, the vice-chair of the EU parliament’s environment committee, said the Guardian’s findings were “explosive”. He added: “The [UAE presidency of Cop28] is a merger of the economic interests of a fossil country with a fundamental transition agenda that should be away from this fossil industry – that will not go well, and [these revelations] already show that it’s not going well.” Al Jaber should be replaced as Cop28 president, Eickhout said. But with time running short before the November summit, he said the UNFCCC secretariat “should now take more control of the entire process” and better reflect the statements made by the UN secretary general António Guterres, who has warned that the climate crisis has put the world on a “highway to hell”. The UNFCCC did not respond to a request for comment. Al Jaber has previously defended his appointment, and told the Guardian in April that his business ties would prove an asset in ensuring the private sector took the necessary action on the climate crisis. The US senator Sheldon Whitehouse, who also co-led the letter calling for the removal of Al Jaber, said: “The [Guardian] reports seem to confirm what many of us have been saying. Sultan Al Jaber will be hard-pressed to separate his role as CEO of Adnoc from his role as the head of the world’s largest diplomatic gathering on climate change. Our window to avert climate disaster is narrowing, and there’s too much at stake for the planet to get this wrong.”