Emma Watson is one of the latest of a growing number of Hollywood stars to reveal she is backing a new campaign to fight sexual harassment across the entertainment industry and other sectors.

The Time’s Up action plan was created in the wake of the sexual assault and harassment allegations which have emerged in recent months.

Other British women in the film industry to show their support for the movement include Kate Beckinsale, Emilia Clarke, Thandie Newton, Karen Gillan, Naomie Harris and Cara Delevingne.

Harry Potter actress Watson shared a post on Instagram with her 41.1 million followers, writing: “The clock’s been ticking on the abuse of power. I stand in solidarity with women across every industry to say #TIMESUP on abuse, harassment, and assault. #TIMESUP on oppression and marginalization.

“#TIMESUP on misrepresentation and underrepresentation.”

She urged people to “sign the solidarity letter” and to donate to the Time’s Up legal defence fund.

More than 300 women across the entertainment industry launched the Time’s Up initiative, including prominent Hollywood stars Reese Witherspoon, Meryl Streep, Shonda Rhimes, Natalie Portman, Eva Longoria and Ashley Judd.

It was unveiled with a full page advert in the New York Times, and it also has a website.

Time’s Up will advocate for legislation to tackle workplace harassment, and the campaign includes a legal fund to help people protect themselves from sexual misconduct.

A letter from the group read: “We particularly want to lift up the voices, power and strength of women working in low-wage industries where the lack of financial stability makes them vulnerable to high rates of gender-based violence and exploitation.”

“The struggle for women to break in, to rise up the ranks and to simply be heard and acknowledged in male-dominated workplaces must end; time’s up on this impenetrable monopoly,” said the letter.

The group is also backing the movement for women to wear black, in solidarity with those who have been sexually harassed, at the Golden Globes.