Michelle Williams has had one of the most ''indelible days'' of her life after Mark Wahlberg donated $1.5 million to Time's Up.

The 37-year-old actress has spoken out after her 'All the Money in the World' co-star agreed to donate the fee he received for reshoots on the movie to the anti-harassment charity, with their shared agency William Morris Endeavor (WME) donating an additional $500,000, following a backlash after it emerged Michelle was paid just $80 a day when they returned to shoot key scenes again after Christopher Plummer replaced Kevin Spacey in the film.

But though it's a day she'll never forget, Michelle insists the actions are not ''about'' her, but a stand for equality.

She also sent her support to Anthony Rapp, whose accusations of inappropriate sexual behaviour against Spacey led to the actor being fired from the project.

She said in a statement: ''Today isn't about me. My fellow actresses stood by me and stood up for me, my activist friends taught me to use my voice, and the most powerful men in charge, they listened and they acted. If we truly envision an equal world, it takes equal effort and sacrifice.

''Today is one of the most indelible days of my life because of Mark Wahlberg, WME and a community of women and men who share in this accomplishment. Anthony Rapp, for all the shoulders you stood on, now we stand on yours.''

When he made his donation, Mark, 46, insisted he supports ''fair pay'' and admitted the discrepancy was an ''important topic''.

He said: ''Over the last few days my reshoot fee for 'All The Money in the World' has become an important topic of conversation. I 100 per cent support the fight for fair pay and I'm donating the $1.5 million to the Time's Up Legal Fund in Michelle Williams' name.''

And WME added in a statement: ''The current conversation is a reminder that those of us in a position of influence have a responsibility to challenge inequities, including the gender wage gap. In recognition of the pay discrepancy on 'All The Money In The World reshoots', WME is donating an additional $500,000 to the Time's Up Legal Fund in Michelle Williams' name, following our $1 million pledge to the organisation earlier this month. It's crucial that this conversation continues within our community and we are committed to being part of the solution.''