International Women's Day on Tuesday celebrated women and their accomplishments, but it also offered a stark reminder of the gender divides in rights, representation and pay.

The day carried the theme "Pledge for Parity" — a phrase and hashtag born out of the World Economic Forum's recent projection that the progress on achieving global gender parity is slowing.

Google's home page on Tuesday featured a video of women and girls dreaming and doing big things. Twitter and Facebook feeds filled with quotes from inspirational women and calls to action.

But the U.N. cultural agency also offered sobering statistics: More than 63 million girls are excluded from school in more than 200 countries across the world. Almost 16 million girls between the ages of 6 and 11 — compared with about 8 million boys — will never get the chance to learn to read or write in primary school "if current trends continue," according to a report from UNESCO's Institute for Statistics.

Women also account for 70 percent of the world's hungry, the U.N. reported, in part because longstanding discrimination has limited their access to food.

President Barack Obama, a father of two daughters, said in a statement that allowing women and girls around the world to rise and achieve their full potential will mean "a brighter, more peaceful and more prosperous future for us all."

Hillary Clinton, vying to become the country's first woman president, tweeted Tuesday that advancing the status of women and girls will make economies grow and nations more secure.

"It's the right — and smart — thing to do," she wrote.

U.N. Secretary-General Ban Ki-moon stressed empowering women as he spoke of preventable deaths during child birth and those who are subjected to "genital mutilation."

Actress Emma Watson, kicking off a weeklong U.N. arts event aimed at initiating a dialogue about gender, said it's not enough for people to rationally understand the necessity of gender equality.

"It's also about making them feel it in their bones," she said.

Some countries treat the day as a holiday, and women could be seen on a sunny Tuesday in the Romanian capital carrying flowers, the traditional gift. Elsewhere in Bucharest, women brandished a banner saying "March 8 is for fighting."

In India, Prime Minister Narendra Modi's call for only female lawmakers to address parliament on Tuesday included silence because there weren't enough women to speak. Of the 543 elected members in India's lower house, 12 percent are women.

In China, International Women's Day is treated as a one-off where state media are fond of publishing photo galleries of "Beautiful Women Reporters" covering a ceremonial legislature.

The Communist Party-run People's Daily made no mention of leadership roles in a front-page editorial Tuesday that said women "can not only help to make homes more pleasant and lively, but also contribute their valuable female perspective and efforts to the progress of the entire society."