BRUSSELS - At least 40 percent of non-executive directors on the boards of big listed companies across Europe should be females by 2020, said the latest legislative proposal from the European Commission on Wednesday.

The Commission, the executive arm of the European Union, aims at breaking the glass ceiling for female elites in around 5,000 publicly listed companies across Europe, excluding small and medium-sized enterprises.

Member states will be obliged to lay down sanctions for companies in breach of the proposal, according to the Commission.

On average, 85 percent of non-executive board members in Europe's listed companies and over 91 percent of executive board members are males, in spite of increasing appeals for more females.

There is much difference between EU member states, with females making up 27 percent of board members in large Finnish companies and only three percent in those of Malta.

The proposal was jointly presented by several vice-presidents of the Commission, including Viviane Reding, Antonio Tajani, Joaquin Almunia and Olli Rehn.

It came after months of reluctance from several EU member states led by the UK and still needs the approval from the Parliament and the EU Council.

Of the 26 commissioners, only about one third are females.

The Parliament has repeatedly called for legislation on equality between men and women in business leadership, while a dozen of EU member states already have relevant legislation.