A total of 1,602 delegates with links to the oil, gas and coal sectors have headed to Belem, equivalent to around one in 25 participants, according to Kick Big Polluters Out (KBPO), which analyzed the list of attendees.

By comparison, hosts Brazil have sent 3,805 delegates.

KBPO's list includes representatives of energy giants ExxonMobil, Chevron, Shell and TotalEnergies, as well as state-owned oil firms from Africa, Brazil, China and the Gulf.

It also includes personnel from a broad range of companies including German automaker Volkswagen or Danish shipping giant Maersk, or representatives of trade associations and other groups.

The Venice Sustainability Foundation is on the list because its members include Italian oil firm Eni.

KBPO also counted Danish wind energy giant Orsted, as it still has a gas trading business, and French energy firm EDF -- most of its power comes from nuclear plants but it still uses some fossil fuels.

The list includes state-owned Emirati renewable firm Masdar.

One of the analysts, Patrick Galey, head of fossil fuel investigations at Global Witness, told AFP that some of the names might appear "surprising" at first sight, but KBPO analyzes data and open-source material to identify links to fossil fuels.

Any renewable company that is a subsidiary of a fossil fuel firm made the list, for instance, because they are "at the beck and call" of their parent group, Galey said.

KBPO considers a fossil fuel lobbyist any delegate who "represents an organization or is a member of a delegation that can be reasonably assumed to have the objective of influencing" policy or legislation in the interests of the oil, gas and coal industry.

TotalEnergies chief executive Patrick Pouyanne defended his presence in Belem when confronted by a Greenpeace activist about the attendance of fossil fuel lobbyists.

"I am not a lobbyist at all... You are very wrong," Pouyanne said.

"I was invited. I came and I believe in dialogue," he added. "I don't think we will make progress on climate through exclusion because otherwise what will happen? We will stay in our corner, we'll make our oil and that's it?"

- 'Common sense' -

KBPO has analyzed COP participant lists since 2021.

COP28 in oil-rich Dubai in 2023 had a record number of participants -- over 80,000 -- but also the most fossil fuel lobbyists ever counted by KBPO at 2,456, or three percent of the total.

In Belem, 3.8 percent of attendees are tied to fossil fuel interests, the largest share ever documented by KBPO.

"It's common sense that you cannot solve a problem by giving power to those who caused it," said KBPO member Jax Bonbon from IBON International in the Philippines, which was recently struck by a devastating typhoon.

"Yet three decades and 30 COPs later, more than 1,500 fossil fuel lobbyists are roaming the climate talks as if they belong here," Bonbon said in a statement.

The numbers could be higher.

According to Transparency International, 54 percent of participants in national delegations either withheld their affiliation or selected a vague category such as "guest" or "other."