The president of the European Commission, Ursula von der Leyen, urged companies on Thursday to promote more women to top positions, even though efforts to introduce binding quotas for European boards have stalled.
European Commission data shows fewer than 7% of top companies' CEOs are women and recent reports suggest that the COVID-19 pandemic may be reversing equality gains in the workplace.
"I won't stop pushing for gender quotas on boards until we get a fair system for all European countries," von der Leyen told the European Parliament's Committee on Women's Rights and Gender Equality.
"Women should always be able to reach for the top, including in private companies," she said.
Von der Leyen singled out for praise three women who led teams that developed the first vaccines against COVID-19, produced by BioNTech, Moderna and AstraZeneca.
"Doctor Oezlem Tuereci, Professor Sarah Gilbert, Doctor Kizzmekia Corbett - some of you may have never heard their names before but we owe them a lot," she said.
Von der Leyen is the first woman to lead the Brussels-based EU executive, which will propose legislation on Thursday to boost pay transparency across the 27-nation bloc in a bid to narrow a persistent gender pay gap.
But such gender equality initiatives have stalled previously, including a 2012 legal proposal calling for listed companies in the EU to fill at least 40% of their non-executive board seats with women.
Some EU countries refused to adopt that target as law.