Protestors flock to anti-Trump Women's Marches

Hundreds of thousands of marchers assembled in Los Angeles, New York, Washington, Chicago, Denver, Boston and other US cities.

Protestors hoisted signs emblazoned with slogans like "Fight like a girl", "A woman's place is in the White House" and "Elect a clown, expect a circus."

The largest demonstrations were in cities where Trump performed poorly at the polls: the Los Angeles mayor said estimated turnout in his city was 600,000, while New York police estimated about 200,000 protesters.

In Manhattan, a diverse crowd descended on Central Park West, the avenue that borders the city's beloved park and arrives at the foot of the Trump International Hotel - part of the magnate-turned-commander-in-chief's real estate empire.

Speakers at the New York rally included activist and actress Rosie Perez and entertainer Whoopi Goldberg, who emphasized that "we are here to say - as women - we're not taking it anymore."

Throngs of demonstrators paraded in Los Angeles, where actress Natalie Portman was among the celebrities pumping up the crowd: "Because of you the revolution is rolling."

The marches aim to build on the movement launched last year when more than three million people turned out nationwide to voice opposition to Trump.

The weekend of demonstrations is aimed at translating enthusiasm into political action with the theme "Power to the Polls" - a message designed to drive voter registrations and maximize women's involvement in the 2018 midterm elections.

The president meanwhile posted a deadpan tweet referencing the rallies protesting his policies, urging people to "get out there and celebrate the historic milestones and unprecedented economic success and wealth creation that has taken place over the last 12 months."