The UK’s fund management lobby group will turn up the heat on companies in the coming months over ethnic diversity in the boardroom, with plans to issue warnings to those that fail to make progress.

The Investment Association, which represents Britain’s £8.5tn asset management sector, has said it will target FTSE 350 companies that fail to disclose the ethnic diversity of their boards or a credible plan to progress towards having at least one director from an ethnic minority background.