Jodie Whittaker, Emma Watson and UK actors pen powerful open letter in support of Time's Up movement against harassment and inequality

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Titled "Dear Sisters", the letter claims that the movement is at a "critical juncture" in the UK.

"The gender pay gap for women in their 20s is now five times greater than it was six years ago. Research in the UK has found that more than half of all women said they have experienced sexual harassment at work. A growing reliance on freelance workforces creates power relationships which are conducive to harassment and abuse. Those engaged in insecure contract work are especially vulnerable to exploitation," it reads.

It goes on to explain that the signatories believe they have a responsibility to "use our power as communicators and connectors to shift the way society sees and treats us" and to promote the vision of an equal society.

"We need to examine the kind of womanhood our industry promotes and sells to the world", it continues, explaining that the eve of the Bafta Awards was chosen to release the letter in the hope of celebrating "this tremendous moment of solidarity and unity across borders by coming together and making this movement international".

"The truth is, we are all workers, and whether we’re in the limelight or in the shadows, our voices matter. With our collective power, we can galvanize others," the letter says.

Claire Foy, Vicky McClure, Eleanor Tomlinson, Caitriona Balfe, Tessa Thompson, Noma Dumezweni, Saoirse Ronan, Charlotte Ritchie and Lily James are also among the extensive list of signatories.

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A second letter, written on behalf of more than 160 activists who work at a number of women's organisations including rape crisis centres and trade unions, was also released.

"We recognise that the ways in which women in the entertainment industry have been silenced mirror the ways that women are silenced by individual perpetrators, by companies, by families, by institutions, by communities, and by the state," it reads. "For each woman in the entertainment industry who has spoken out, there are thousands of women whose stories go unheard. These are not isolated incidents. This is about power and inequality, and it is systemic."

Gemma Arterton is one of the many signatories who will bring activists to the 2018 Bafta Award ceremony. The Observer reports that she will be accompanied on the red carpet by two former sewing machine operators, Eileen Pullen and Gwen Davis, whose 1968 walk-out from the Ford Dagenham plant inspired the film Made in Dagenham.

“We’re pressing for change in our industry, and we welcome the fact the UK industry has come together and developed principles and guidance which puts tackling harassment in the workplace on the agenda for everyone," said Arterton. "We are only now waking up to the full scale of systematic abuse, inequity and sexual harassment based on gender and power – abuse that hurts us all. Today we stand in unity with others in zero tolerance of this abuse.”

The women have also established a new UK Justice and Equality Fund, which aims to provide advice and support to those affected and advocate for the prevention of further abuse and inequality.