Positive action should be taken to ensure equal representation of women in Parliament and in boardrooms, Cherie Blair has said.
Mrs Blair compared the "slow" progress of women's rights in the UK to the "tremendous strides" taken by emerging democracies such as Tunisia.
She said voluntary efforts inspired by Lord Davies' recommendation to get 25% of women on FTSE 100 boardrooms by 2015 have led to progress but need to be "dramatically accelerated".
She also criticised the "reticent" attitudes which prevent more action being taken to increase the number of female MPs in Parliament.
"Equal representation does not just lead to good democracy, it is democracy," she said.
In a speech given under her professional name of Cherie Booth QC at Chatham House in London, the leading human rights lawyer said that achieving gender parity is "both a legitimate aim and a necessary character of a democratic state".