The head of UN Women says world leaders attending an annual meeting on the status of women have a "once-in-a-lifetime opportunity" to improve the lives of women and girls.

Phumzile Mlambo-Ngcuka says that implementing sustainable development goals endorsed by U.N. member states last year is crucial to advancing gender equality.

The United Nations on Monday kicked off a two-week session of the Commission on the Status for Women, with a focus on the connection between women's empowerment and sustainable development.

The global development goals include Goal 5, which calls for gender equality by 2030. Other goals include elimination of poverty and hunger, quality education and clean water and sanitation.