Fund groups will vote down management proposals at public companies which fail to promote women to board level, the Investment Association has warned.
'A number of key investors have told us that they will vote against AGM resolutions on the grounds of gender representation,' said Chris Cummings, chief executive of the IA.
'With the AGM season now in full swing, companies who are falling short should take urgent steps to outline what they plan to do to increase diversity.
'The body of research is clear: firms with a diverse management team and pipeline make better decisions and drive innovation.'
The IA and the advisory body of the Hampton-Alexander Review, the government body investigating gender in business, have written to 14 FTSE 100 businesses demanding that they explain a lack of progress.
Recipients include BP and Smurfit Kappa, which both have all-male executive committees, and Persimmon and Tui, which have fallen well short of the Hampton-Alexander target of women in 33% of board roles.
They also singled out a further 11 FTSE 250 businesses, such as Sports Direct and Stobart Group, which have all-male boards, and a further 10 businesses, such as AA, J D Wetherspoon and Wizz Air, which failed to report gender diversity data.
Sir Philip Hampton, chair of the Hampton-Alexander Review said: ‘Whilst the majority of FTSE companies are taking great strides to address the lack of women on boards and in their leadership teams, it is disappointing to see a significant minority of companies still making slow or no progress.
'The gap between those working hard to improve gender balance and those doing very little, has never been more obvious.
‘All FTSE companies adrift from 33% women’s representation on their Boards and in leadership, need to rise to today’s challenge from the investment community and take swift action to address the lack of women in their top teams.’