VANCOUVER -- Gender equality is under attack and, in the age of social media, it's never been easier to taunt and spread abhorrent views, Prime Minister Justin Trudeau told a global conference on the issue Monday.

Trudeau, who was in Vancouver for the opening address of Women Deliver 2019, said that hatred is creeping in the public debate, with interest groups trying to roll back women's rights, while politicians are giving into the public pressure.

"The rights we enjoy in Canada, and the rights so many have enjoyed around the world, are not guaranteed. Progress can backslide," Trudeau said.

"We're seeing it happen. Gender equality is under attack, and I can only imagine how hard it is to be a feminist on the front lines."

The prime minister didn't say what he was referring to, although last week he said he planned to talk to U.S. Vice-President Mike Pence about the growing number of American laws that restrict abortion.

The Trump administration has also reinstated a policy known as the "global gag rule," which bans U.S. federal funding for non-governmental organizations abroad that provide abortion services. Shortly after the U.S. adopted the rule in 2017, the Trudeau government committed $650 million for sexual and reproductive health and rights worldwide.

Trudeau said the history of women's rights shows that every step forward is met by another push back, and women are still routinely facing misogyny, racism and hatred.

He said politicians are "shamefully" campaigning to undo women's hard-won victories.

"That's a daunting reality to face. My friends, we are not powerless. It's up to us to fight back," he said.

He also spoke to the crowd about the National Inquiry into Missing and Murdered Indigenous Women and Girls, saying Canada can and must do better to end violence against all women.

His remarks were interrupted by a woman in the crowd who cried out, "Then do something!"

Another yelled, "Shame!"

Despite the brief outburst, the crowd loudly applauded when he acknowledged that the report concluded that violence against Indigenous women amounted to nothing less than a genocide.

"Let me be clear, our government will always be your partner, willing to admit when mistakes are made and working very hard to build a better future for all our children," Trudeau said.

"My friends, I know and you know that we can't take our foot off the pedal, not even for a moment. There's simply too much at stake. Canada's leadership isn't going anywhere."

Women Deliver is a global advocate for gender equality and the health, rights and well-being of girls and women. The four-day conference is billed as the world's largest event advocating for those rights.

The conference was attended by world leaders, including the presidents of Kenya, Ghana and Ethiopia, who joined Trudeau for a panel discussion following his speech.

Panel moderator Lyse Doucet, a BBC journalist, commended Trudeau for being one of the first world leaders to describe himself as a "feminist" and bring in a gender-equal cabinet.

But she noted he had a "tough year," given that he brought "tough women" into his cabinet, and asked how it had affected his feminism.

Former cabinet ministers Jody Wilson-Raybould and Jane Philpott were kicked out of the Liberal caucus this year after they alleged the Prime Minister's Office had pushed for Quebec engineering firm SNC-Lavalin to avoid a criminal trial.

Trudeau said the experience has increased his feminism and made him think differently about it.

"Feminism and diversity and inclusion is not about making things easier. It often makes things a little more difficult," he said. "To have strong voices sticking up for different perspectives means you're going to get challenged, means you get to challenge back, and you get to try and figure out what the right path is forward.

"No one person has the monopoly on all the right answers, regardless of their gender, regardless of their background, regardless of their position as prime minister."