Secretary-General Antonio Guterres called himself "a proud feminist" Monday and said all men should support women's rights and gender equality.

His statement was loudly applauded by hundreds of women and a sprinkling of men at the opening of the annual two-week meeting of the Commission on the Status of Women, a U.N. body that Guterres called "vital to end the stereotypes and discrimination that limit women's and girls' opportunities."

The U.N. chief said changing "the unequal power dynamics" that underpin discrimination and violence against women is "the greatest human rights challenge of our time" — and a goal that is "in everyone's interests."

"Discrimination against women damages communities, organizations, companies, economies and societies," he said. "That is why all men should support women's rights and gender equality. And that is why I consider myself a proud feminist."

Guterres added that this is "a pivotal moment for the rights of women and girls," with the issue being discussed around the globe in the #MeToo and #Time'sUp movements.

As examples of the male-dominated world and male-dominated culture that needs changing, he said, "Women are pioneering scientists and mathematicians — but they occupy less than 30 percent of research and development jobs worldwide."

And despite women being accomplished artists, writers, musicians and filmmakers, this year 33 men took home Oscars at the Academy Awards, but only six women did, he said.

The theme of this year's U.N. meeting, which ends March 23, is "Empowering Rural Women and Girls." Guterres called such women "particularly marginalized."

According to UN Women, rural women do much of the work but fare worse than rural men or urban women.

"Less than 13 percent of landholders worldwide are women, and while the global pay gap between men and women stands at 23 percent, in rural areas, it can be as high as 40 percent," UN Women says.

Ireland's U.N. ambassador, Geraldine Byrne Nason, the commission chair, said its work will focus on these women "who are furthest behind" and are "disproportionately affected by violence, poverty, climate change and hunger."

"Often their predicament quite simply shames us," she said.

"We want to make a difference. We have had enough rhetoric. Time is up for the debates that are long on promises and short on delivery," Byrne Nason said. "We are on the move to bring a tangible result — one that will impact on the lives of women and girls in rural areas."

UN Women Executive Director Phumzile Mlambo-Ngcuka told the opening session that almost one-third of employed women worldwide work in agriculture and there are 400 million women who are farm workers.

"Half of rural poor women in developing countries have no basic literacy, and 15 million girls of primary school age will never, never get the chance to learn to read or write in primary school," she said.

A rural girl is "twice as likely to be married as a child" compared to an urban girl, she added.

Mlambo-Ngcuka warned that progress toward gender equality is slowing and some gains are even reversing.

She pointed to the World Economic Forum's 2017 "Global Gender Gap Report," which found the gap between women and men widening in health, education, politics and the workplace for the first time since the forum's research started in 2006.

"It predicts that it will take — and listen to this — 217 years before we achieve gender parity," Mlambo-Ngcuka said, stressing that this can't be allowed to happen.

"It has never been so urgent to hold ourselves and leaders accountable for the promises to accelerate progress," she said. "The 'Me Too' movement and 'Time's Up' has also showed us change can happen fast — and that women must be believed. This is a moment that we intend to sustain for all."