David Davis has been urged to begin the hunt for a dedicated chief scientific adviser at the Department for Exiting the European Union "without delay" or risk undermining evidence-based policy.
MPs on the Science and Technology Committee last month warned of uncertainty in the scientific community over Brexit, calling on the government to reassure EU scientists and researchers working in the UK that they would be allowed to stay regardless of the outcome of withdrawal negotiations.
The committee also said it was "not convinced" that the UK's science and research sectors were "at the heart of DExEU's thinking and planning for Brexit", calling on the department to recruit a chief scientific adviser "as a matter of priority".
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Each government department has its own chief scientific adviser, and while DExEU had previously told MPs that a role had been advertised for, ministers have since indicated that they are more likely to instead draw on the combined resources of the Government Office for Science.
DExEU minister Robin Walker told a Commons debate this week that the department was "working closely" with Sir Mark Walport, the government's chief scientific adviser "to ensure that we have access to the expertise that we need".
That answer failed to pacify Stephen Metcalfe (pictured), the Tory chairman of the science committee, who has now written to Davis directly to warn that drawing on cross-government help "will not be enough" as the department formulates the UK's Brexit negotiation position.
"I am sure that DExEU ministers and the minister for universities, science, research and innovation will continue to liaise on the science agenda, but it remains fundamentally important that ministers across government get the best possible advice; a role that externally-recruited expert CSAs are specifically designed to fill," Metcalfe writes.
Metcalfe points out that Government Office for Science guidance makes clear that chief scientific advisers are appointed to ensure that ministers and top officials are presented with "robust joined-up evidence" that is "at the core of decisions within departments and across government".
He adds: "We look forward to receiving the government's response to our report in the new year, but given the urgency involved in this issue I would ask that in the meantime you give renewed attention to the need for a DExEU CSA and begin the recruitment process without delay."