Shareholder efforts to change auditing practices at the UK’s largest companies are gathering pace with news that the £34bn Universities Superannuation Scheme has doubled the size of an investor consortium set up last autumn to push for reform.

The USS-led initiative was launched with around a dozen signatories but its ranks have since swollen to 34 investor groups with assets of over €2 trillion under management, according to latest figures from the UK's second-largest private retirement scheme.