Rallies in more than 250 US cities saw demonstrators denounce Mr Trump’s views on immigration, abortion, LGBT and women’s rights on the anniversary of his inauguration.
Adele, Natalie Portman, Scarlett Johansson and Whoopi Goldberg were among a host of celebrities who joined the walks, which also voiced support for campaigns against sexual misconduct following the Harvey Weinstein scandal.
Many protesters carried signs with anti-Trump messages including “Real news, fake president”, while in Oklahoma, demonstrators chanted: “We need a leader, not a creepy tweeter!”.
Similar protests were also taking place in cities around the world, with a women’s march planned in London on Sunday.
Responding to the protests, Mr Trump wrote on Twitter that it was a “perfect day for all women to march” to “celebrate the historic milestones and unprecedented economic success and wealth creation that has taken place over the last 12 months”.
Beautiful weather all over our great country, a perfect day for all Women to March. Get out there now to celebrate the historic milestones and unprecedented economic success and wealth creation that has taken place over the last 12 months. Lowest female unemployment in 18 years!
— Donald J. Trump (@realDonaldTrump) January 20, 2018
An estimated 500,000 protesters gathered in downtown Los Angeles on Saturday where Oscar-winning actress Viola Davis spoke about her experience as a victim of sexual assault.
Addressing the crowd, Davis said: “I’m always introduced as an award-winning actor but my testimony is one of poverty, my testimony is one of being sexually assaulted and very much seeing a childhood that was robbed from me.
“I know that the trauma of those events are still with me today and that’s what drives me to the voting booth, that’s what allows me to listen to the women who are still in silence.”
Desperate Housewives actress Eva Longoria criticised the “sexist, racist rhetoric” coming out of the White House as she urged protesters to seize the momentum to fight for equality.
“As we build upon the momentum of MeToo and Time’s Up in this movement, we women have the world’s attention so let’s seize this moment and catalyse a permanent and cultural shift towards fairer and equal treatment in the workplace,” she said.
Singer Adele shared a photo on Instagram of herself, Cameron Diaz and Jennifer Lawrence holding placards at a women’s march as she issued a “power to the peaceful” rallying cry.
The most influential people in my life have always been women. My family, my friends, my teachers, my colleagues, and my idols. I am obsessed with all the women in my life. I adore them and need them more and more every day. I am so grateful to be a woman, I wouldn’t change it for the world. I hope I’m not only defined by my gender though. I hope I’m defined by my input to the world, my ability to love and to have empathy. To raise my son to be a a good man alongside the good man who loves me for everything I am and am not. I want what’s best for people, I think we all do. We just can’t agree on what that is. Power to the peaceful, power to the people x #womensmarch2018
A post shared by Adele (@adele) on Jan 20, 2018 at 1:26pm PST
“The most influential people in my life have always been women,” she wrote.
“My family, my friends, my teachers, my colleagues, and my idols. I am obsessed with all the women in my life. I adore them and need them more and more every day.”
She added: “Power to the peaceful, power to the people.”
Protesters in Rome voicing support for the MeToo movement included actress Asia Argento, who accused movie mogul Weinstein of sexual assault, which he denies.
Several hundred protesters also gathered in Palm Beach, Florida near Mr Trump’s Mar-a-Lago home.
Hillary Clinton, who lost out to Mr Trump in the 2016 US election, said the women’s marches were “a testament to the power and resilience of women everywhere”.
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In 2017, the Women’s March was a beacon of hope and defiance. In 2018, it is a testament to the power and resilience of women everywhere. Let’s show that same power in the voting booth this year. #PowerToThePolls
— Hillary Clinton (@HillaryClinton) January 20, 2018
She also urged people to show the “same power in the voting booth this year” ahead of November’s mid-term elections.
Saturday’s marches marked a year since more than one million worldwide rallied on Mr Trump’s first day in the White House.