Jessica Chastain was ''shocked'' when she heard about the pay gap Octavia Spencer was experiencing.

The 41-year-old actress helped negotiate a salary five times higher than the original offer given to Octavia for her work in an upcoming project they are due to star in together, and Jessica has said she was horrified to hear of the pay disparity as she believed Octavia should be ''compensated fairly'' for her work.

During an appearance on the 'Today' show on Tuesday (26.06.18), Jessica said: ''Of course I knew women of colour got paid less, I mean of course I knew that. But I just assumed, which is the dangerous thing, I assumed that a woman like Octavia Spencer would be compensated fairly for the work she's done, for the awards she's received.

''When she told me what her salary had been, that's what really shocked me. And I thought, okay well we're gonna tie ourselves together in this next film.''

It isn't the first time the 'Molly's Game' has spoken about her help in securing a fair wage for the 46-year-old star, as she previously admitted she ''cares more'' about Octavia salary than her own.

She said: ''I knew women of colour got paid less than Caucasian actresses.

''What I didn't know is someone of Octavia's level, who had an Oscar and two Oscar nominations, how much less she would be getting paid.

''When she told me what she was making, that's what really made me go, 'Hold up, that doesn't compute in my brain.'

''This is the God's honest truth - I care more about what Octavia's getting paid than what I'm getting paid. Because I've got a great life. I am more concerned about her than I am about me. Equal pay for equal work!''

And the 'Hidden Figures' star has praised her friend as her ''biggest cheerleader'' and ''most vocal advocate''.

Octavia said: ''I shared a personal story [with Jessica] about what [financial] success has meant for me and most women of colour in comparison to our white counterparts.

''I told her about the gross disparity in our salaries. She provided a much-needed shoulder and listened. And then she did what she always does: She took up my cause and made it her own.

''As a friend, she's your biggest cheerleader; but as a colleague, she's your most vocal advocate.''