Livestock groups have been lobbying the UN to support more meat and dairy production before a high-profile summit on food sustainability, documents reveal.

Most experts agree that livestock are responsible for at least 14% of global emissions, while a study published last week found the use of animals for meat causes twice the planet-heating gases that plant-based foods do.

The UN Food Systems Summit (UN FSS), taking place this week in New York, aims to make global agricultural systems more sustainable, billing itself as a transformational “people’s summit”.

But documents obtained by Greenpeace Unearthed – the investigative arm of environmental NGO Greenpeace – and seen by the Guardian, show livestock industry bodies threatening to withdraw if others in their discussion group at the summit do not share their “common goal”.

In the months leading up to the summit, discussion groups – known as clusters – worked to produce position papers offering sustainable food system solutions.

In one draft paper, dated 15 June, members of the “sustainable livestock” cluster stated that “advances in intensive livestock systems” mean they can “contribute to the preservation of planetary resources and effective delivery of nutrition”.

Environmental and other experts have advised however that lower levels of animal protein production and consumption are critical to reducing climate breakdown and protecting the environment.

At almost the same time as the livestock group’s draft paper was released, 11 new members were added to the cluster, including a farm animal welfare NGO and environmental scientists. The addition sparked a letter of complaint to the UN from some of the original members, describing the new members as wishing “to further an ideological anti-livestock stance”.

The letter, dated 26 June, which threatened the signatories’ withdrawal, said although it understood the “need for inclusiveness”, to function well “the group must share a common goal” and described the addition of new members as “a clear breach of the trust”.

It was signed by the International Meat Secretariat, the International Poultry Council, Global Dairy Platform, the International Dairy Federation, the Global Roundtable for Sustainable Beef, the International Egg Commission and the International Feed Industry Federation and an animal pharmaceutical representative called HealthforAnimals. As yet, no members have withdrawn.

Michael Fakhri, UN special rapporteur on the right to food, criticised the summit’s failure to consult and involve voices from outside the meat industry from the beginning. “It started with the meat industry itself, and then included people who wish to softly transition from the current system. Only towards the end were more critical voices invited.”

One of the 11 new additions to the cluster, Philip Lymbery, chief executive of NGO Compassion in World Farming, said he found the original members to be “heavily weighted toward industry interests”. On joining, Lymbery said he found the solution offered by the cluster was “substantially more livestock production” with some additional “technical innovations” that would make production more sustainable.

Another new member, Matthew Hayek, assistant professor of environmental studies at New York University, said he believed the UN FSS should not have given “incumbent industries a platform to deny or minimise the scientific consensus”.

Of the three position papers produced by the cluster for the summit, only one describes the disadvantages of industrial farming and clearly states that “a significant reduction in global consumption of meat and dairy is needed” to meet the Paris climate targets.

“Our perspective on reducing consumption was limited to only one of three solution papers; the other two still primarily emphasise [livestock] industry-aligned solutions,” Hayek said.

One of the signatories of the livestock group’s letter of complaint, Hsin Huang, secretary general of the International Meat Secretariat (IMS), said he found the idea of the IMS lobbying the UN FSS “laughable”.

Disputing the claim that livestock industry groups were the first to be contacted by the UN FSS, Huang said the IMS and other private livestock groups were only formally invited to join the livestock cluster on 4 June this year – although he said “voluntary clusters” had been working before that.

Asked about reducing animal numbers, particularly of intensively farmed animals in developed countries, Huang said industrial agriculture had answered customer needs by delivering safe, cheap foods with a longer shelf life.

He added that the IMS was “extremely supportive of better animal welfare” and not “necessarily against the idea of reducing” animal numbers, but it was a complicated issue.

For example, he said, reducing animal numbers “in developed countries will only lead to more animals produced in less efficient systems in developing countries. And that will make emissions issues, environmental issues, resource use issues and welfare problems worse.”

A joint statement from the Global Dairy Platform and the International Dairy Platform did not directly address the lobbying issues, nor other criticisms raised, but said: “The global community needs the recommendations made by the Food Systems Summit to be balanced and not based on ideology or tradeoffs which could put long-term food security and livelihoods at risk.”

Asked when the livestock cluster discussions had begun, and which groups were invited first, the UN said in an emailed statement that the “Sustainable Livestock Solutions Cluster evolved during the open public engagement process that took place in two ‘phases’ between December 2020 and May 2021.”

The email confirmed that new members were introduced to the livestock cluster in June but did not give a date. It added that as “a solutions summit” the UN food summit “aimed to create a space for new and sometimes difficult conversations, grounded in science,” and as a “people’s summit, the approach was to ensure all voices are heard, including those from the most marginalised farmers to governments to private companies, accepting that sometimes there are divergent viewpoints.”

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