Updated January 02, 2018 12:13:15

Photo: Actress Reese Witherspoon founded Time's Up with 300 other Hollywood heavyweights. (Reuters: Danny Moloshok)

Reese Witherspoon, Nicole Kidman, Margot Robbie and Jennifer Aniston are among hundreds of Hollywood women who have formed an anti-harassment coalition called Time's Up.

The initiative was launched with an open letter vowing support for women in the entertainment business and beyond, from janitors to healthcare workers.

The letter ran as a full-page ad in The New York Times and Spanish-language newspaper La Opinion.

Time's Up will include a legal defence fund for victims across different industries, reportedly backed by $US13 million ($16.7 million) in donations, and will advocate for legislation combatting workplace harassment.

This followed a letter of solidarity from 700,000 female Latina farmworkers who expressed their support for those in the entertainment industry who suffered sexual harassment and abuse in the workplace — a reality they said they know "far too well".

"Even though we work in very different environments, we share a common experience of being preyed upon by individuals who have the power to hire, fire, blacklist and otherwise threaten our economic, physical and emotional security," the letter, published in November, said.

The Harvey Weinstein effect is making more than ripples.

"Like you, there are few positions available to us and reporting any kind of harm or injustice committed against us doesn't seem like a viable option.

"Complaining about anything — even sexual harassment — seems unthinkable because too much is at risk, including the ability to feed our families and preserve our reputations."

Time's Up has described the letter as "powerful", and said it will focus on lifting the "voices, power, and strength of women working in low-wage industries where the lack of financial stability makes them vulnerable".

Time's Up is backing the movement for women to wear black, in solidarity with those who have been sexually harassed, at Sunday's Golden Globes ceremony.

Donors to Time's Up's defence fund range from Meryl Streep and Taylor Swift to JJ Abrams and Viola Davis.

Other founding members of the group include Natalie Portman, Naomi Watts, Alyssa Milano, Amy Schumer, Ashley Judd, Blake Lively and Michelle Pfeiffer.

Dozens of men have faced harassment and assault allegations in recent months including Harvey Weinstein, Charlie Rose and Kevin Spacey.

ABC/AP

Topics: sexual-offences, law-crime-and-justice, community-and-society, arts-and-entertainment, united-states

First posted January 02, 2018 11:51:20