The risk stems from the fact that sustainability claims are not audited externally, NAO said.

Report (apols for govt-report speak): “Identifying and prioritising climate-related risks will often require skills and expertise from multiple functions including sustainability, finance, risk, policy and delivery. For bodies with material climate-related risks, quantified scenario analysis may also require specific climate modelling expertise.

Senior leadership and public sector decision-makers will also need sufficient understanding to engage with the technical and uncertain information included in sustainability disclosures, alongside other risks.

Without integrated governance arrangements and cross-functional capability, TCFD-aligned (Task Force on Climate-related Financial Disclosures -aligned) disclosures are at risk of being superficial. Cross-cutting risks, especially transition risks, may go unrecognised or unaddressed.

2.27 Unless and until sustainability reporting is subject to external assurance, there is also a risk that disclosures present an unfairly positive view, or greenwash, the performance of central government bodies.

While Accounting Officers have a responsibility to ensure that annual reports are fair, balanced and understandable, without external scrutiny public bodies may not be sufficiently motivated to focus concisely on the most relevant information to users.

This would reduce the effectiveness of TCFD-aligned disclosures in providing greater transparency and accountability.”