A spokesman for Gove told Unearthed: “The government and the environment secretary have been very clear that food safety and animal welfare standards will not be weakened after Brexit.

“We will never be swayed on this. There will no chlorinated chicken entering the UK and we will retain the precautionary principle. That position won’t change whatever any think tank recommends,” he continued.

Green Party leader Caroline Lucas said: “It’s deeply concerning to see an organisation as influential as the Institute for Economic Affairs is willing to take cash from US agribusiness in return for favourable reports.”

“But what’s more worrying is Michael Gove’s apparent enthusiasm for a project authored by a leading climate change sceptic whose love of dangerous pesticides is well-documented. If the Government wants research-backed policies, ministers would do well to rely on their own independent civil servants,” she continued.

Ridley told Unearthed that the report was about innovation in agriculture rather than agriculture after Brexit and added that its aim is not to influence Defra officials but to “inform all debate on the topic.”

‘Substantial content’

The IEA, which is registered as an educational charity, does not disclose its donors, arguing that it is under no moral or legal obligation to do so. In 2016, the charity’s trustees told the regulator it only accepts research sponsorship from “individuals or trusts who do not have a vested commercial interest in the topic”, the Charity Commission wrote.

“[T]he trustees take considerable efforts to ensure that whatever the source of funding, IEA’s research is independent,” the commission wrote.

But Littlewood suggested donors’ interests could help shape its reports.

When asked by the Unearthed reporter whether his client, a fictional investor in US beef, would be able to fund the report and ensure its specific concerns were covered, Littlewood responded: “Oh sure and, and absolutely and we, I don’t mind our donors affecting us on salience.”

He continued: “We would assume that donors are giving us money because we are covering areas of their interest and we can make those undertakings and guarantees no problem at all… And beef is actually, it is actually an area of interest, an area that we do genuinely happen to be interested in.”

And he added: “To give you an example, we would take money from alcohol companies. We would go to alcohol companies and say we, we want to write about the cost of living being too high and actually alcohol consumption is not costing the National Health Service as much money as they often complain.”

He added that the IEA does not let donors change a report’s conclusions, but confirmed that there would be prominent “substantial content” covering their areas of interest.

Responding to the allegation that Littlewood offered the prospective donors the chance to influence the report, a spokesperson for the IEA told Unearthed: “We have no evidence or reason to believe this is the case. Mark was clear that corporate donors do not alter the conclusions of IEA work.”

“The IEA is currently working on a report on agricultural innovation, which was commissioned prior to the meeting outlined. As previously mentioned, we would carry out this work regardless but obviously do fundraise to cover the production and distribution costs of our output,” she continued.