Emma Thompson donated £500 ($700), while £1,000 ($1,400) was also donated each by Dr Who star Jodie Whittaker, Lionsgate CEO ZygiKamasa, British actress Tamsin Greig, The Girl With the Dragon Tattoo actress NoomiRapace and Gugu Mbatha-Raw, who starred in the critically-acclaimed "San Junipero" episode of Black Mirror.
Watson, 27, who played Hermione Granger in the eight-film "Harry Potter" franchise from 2001 to 2011, is reportedly worth 39 million pounds according to last year's Sunday Times Rich List.
Explaining that sexual harassment is far from just an American problem, the letter states, "Here in the United Kingdom, this movement is at a critical juncture".
The BAFTA Awards are on BBC1 tonight at 9.00pm. Watson and other high profile actors are supporting to "end the culture of harassment, abuse and impunity".
The letter was published ahead of the British Academy Film Awards on Sunday night, when stars are expected to repeat the protest staged at last month's Golden Globes awards and wear black in a show of solidarity with victims. This movement is intersectional, with conversations across race, class, community, ability and work environment, to talk about the imbalance of power.
It highlights problems in Britain such as the gender pay gap and changes to work that often make it more insecure.
"While we know women are disproportionately affected by this abuse, we also know there are men in our industry and others that have been subjected to harassment and abuse as part of this system of patriarchal power".
Women in Hollywood band together to fight sexual harassment IBTimes US.
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While some users prefer the old method, this will undoubtedly stop some users from stealing images and photos. Getty Images, a large database company for high-quality photos, is the main reason the button was removed.
"In 2018, we seem to have woken up in a world ripe for change".
"We believe we need to use our power as communicators and connectors to shift the way society sees and treats us", they said.
"We need to examine the kind of womanhood our industry promotes and sells to the world".
The letter argues that "there is no question that Time's Up should be and will be a global movement".
"It's easy to dismiss harassment and abuse as being caused by "one or two really, really bad men" but the United Kingdom statistics point to a much bigger and more structural problem".
The new fund closely mirrors the Time's Up campaign propelled by the U.S. entertainment industry to tackle harassment and sexism. Over $2 million has been raised for the fund thus far.
As we approach the Baftas - our industry's time for celebration and acknowledgment - we hope we can celebrate this tremendous moment of solidarity.
A second letter signed by more than 160 activists, academics and service providers welcomes the involvement of the stars.