Patricia Arquette has stood by her powerful Oscar acceptance speech in a series of tweets calling for equal pay for women.

'Women have been basically paying a gender tax for generations,' she tweeted on Monday, hours after accepting the Academy Award for Best Supporting Actress for Boyhood.

As she collected the award, she told the star-studded crowd: 'To every woman who gave birth, to every taxpayer of this nation. It's our time to have wage equality once and for all in the United States of America.'

Following the speech, some viewers lashed out at Arquette for failing to address Hollywood's lack of racial diversity - and she responded to them in her tweets on Monday afternoon.

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Speaking out: As she accepted her Oscar for Best Supporting Actress for Boyhood, Patricia Arquette gave a rousing speech at Sunday's Academy Awards ceremony calling for equal pay for women

Outspoken: Meryl Streep and Jennifer Lopez both cheered as she delivered the speech on Sunday night

'Wage equality will help ALL women of all races in America. It will also help their children and society,' she wrote on her Twitter page.

'Guess which women are the most negatively effected in wage inequality? Women of color. #Equalpay for ALL women. Women stand together in this.'

Her speech had received raucous applause, in particular from fellow Oscar winner Meryl Streep, who punched the air and shouted 'yes!' while Jennifer Lopez clapped enthusiastically.

It came two months after the Sony hack revealed that Jennifer Lawrence and Amy Adams were paid significantly less than their male co-stars in 'American Hustle': Bradley Cooper, Christian Bale and Jeremy Renner.

After the leak, Sony co-chair Amy Pascale defended the difference in pay. She has now stepped down from the position.

Defense: In a series of tweets on Monday, Arquette backed up her speech and said she wanted equal pay for all women across all races - after some people slammed her for failing to highlight racial inequalities

'I run a business,' she said at the Women in the World event in San Francisco two weeks ago. 'People want to work for less money, I'll pay them less money. I don't call them up and go, can I give you some more? [These women] have to walk away. People shouldn’t be so grateful for jobs.'

But while some supported Arquette's decision to spotlight pay gaps, other viewers were not so impressed at the lack of diversity at the awards.

PopCultureHusky tweeted: 'Patricia Arquette speaks out for equal pay for women, I wish there were some black folks to speak out on equal...forget it #OscarsSoWhite.'

Michelle Simon posted: '#AskHerMore What about equal rights for black people, Patricia Arquette?'

Much of the chatter going into the Oscars was about the lack of diversity in the Academy's choices, specifically the dearth of nominations for civil rights movie, Selma.

But while there were plenty of references to racial justice during the ceremony - drawing tears from the movie's David Oyelowo at one point - issues mentioned in acceptance speeches also touched on Alzheimer's and Lou Gehrig's disease.

Political points came thick and fast from the moment the curtain came up.

Oscars host, Neil Patrick Harris, started with a barb about the lack of nominations for black actors, saying: 'Tonight we celebrate Hollywood's best and whitest, sorry … brightest.'

John Legend and rapper Common, who won Best Original Song for Glory in the film Selma, used their joint speech to link 19th-century slavery with the number of black men in U.S. prisons today.

The musicians also referred to the protests in Ferguson, Missouri last year which were sparked by the killing of unarmed black teen Michael Brown by a white cop.

Legend said: 'Selma is now because the struggle for justice is right now. We know that the Voting Rights Act they fought for 50 years ago is being compromised right now in this country today. We know that right now, the struggle for freedom and justice is real.

'We live in the most incarcerated country in the world. There are more black men under correctional control today then were under slavery in 1850.

Rapper Common (pictured left) and singer-songwriter John Legend (right) used their Oscar acceptance speech to highlight the ongoing civil rights struggle in the U.S.

Best Actor winner Eddie Redmayne (pictured right), who won for his portrayal of Stephen Hawking in The Theory of Everything, said: 'This Oscar belongs to all of those people around the world battling ALS'. Left, Best Actress winner Julianne Moore said her movie, Still Alice, shines the light on Alzheimer's

'We are with you, we see you, we love you, and march on.'

Laura Poitras used part of her speech accepting the award for best documentary for Citizenfour to note that 'the disclosures that Edward Snowden reveals don't only expose threats to our privacy but to our democracy'.

Birdman director Alejandro Gonzalez Inarritu called for respect for Mexican immigrants during his Oscars' acceptance speech on Sunday

But when the camera went back to Oscar host Neil Patrick Harris, he was quick to make a reference to the controversy surrounding Snowden: 'The subject of Citizenfour couldn't be here for some treason.'

Snowden is living in Russia to avoid arrest here. His supporters think he's a hero - critics think he's a traitor.

Sean Penn raised eyebrows with a reference he made to green cards in presenting the Oscar for best picture to Alejandro Gonzalez Inarritu for 'Birdman,' but the two are friends and Inarritu interpreted the comment as a joke.

'Who gave this son of a b**** his green card?' Penn said.

Inarritu, who is Mexican, hugged Penn warmly, and joked that the U.S. government might now impose immigration rules on the Academy: 'Two Mexicans in a row, that's suspicious.'

Alfonso Cuaron, another Mexican director, won for Gravity last year.

On a serious note, Inarritu said, he hoped the 'latest generation of immigrants ... can be treated with the same dignity and respect of the ones who came before and built this incredible immigrant nation'.

However viewers were not so quick to forgive Penn's remarks.

TV host, Mario Lopez, was one of the first on Twitter to express his outrage.

He tweeted: '''Who gave this guy a green card?" Sean Penn talking about a Mexican dude to a room full of British & Australian people...'

Director Jose Antonio Vargas wrote: 'I've traveled to 45 states and head people say "illegal" and "Mexican" interchangeably. That's why green card joke was tone deaf #Oscars.'

Journalist, Mariana Atencio, posted: 'And yet nobody asked Eddie Redmayne who gave him his green card...#Iñarritu #Oscars2015.'

(From left to right) Dirk Wilutzky, Laura Poitras, Glenn Greenwald, Lindsay Mills and Mathilde Bonnefoy accept the Best Documentary Feature for Citizenfour about Edward Snowden

In accepting the award for best actress for Still Alice, Julianne Moore said the movie shines a light on Alzheimer's.

She said: 'People with Alzheimer's deserve to be seen.' She also noted that Richard Glatzer, who directed and wrote it with Wash Westmoreland, has ALS, also known as Lou Gehrig's disease.

We live in the most incarcerated country in the world. There are more black men under correctional control today then were under slavery in 1850. We are with you, we see you, we love you, and march on Oscar winner John Legend

Eddie Redmayne, accepting the best actor award for his portrayal of Stephen Hawking in 'The Theory of Everything,' said: 'This Oscar belongs to all of those people around the world battling ALS.'

Graham Moore, who won the Oscar for best adapted screenplay for The Imitation Game, said in his acceptance speech that he had tried to kill himself as a teenager.

'When I was 16, I tried to kill myself because I felt weird and I felt different and I felt like I did not belong,' he said.

'I would like this moment to be for the kid out there who feels like she's weird and different and feels like she doesn't belong... Yes, you do.'

Backstage, Moore said he saw the public moment as a rare opportunity for a writer and figured that 'I might as well use it to say something meaningful.'

Earlier in the ceremony, Dana Perry mentioned that her son had killed himself. Perry made her comments in accepting the Oscar for best documentary for 'Crisis Hotline: Veterans Press 1.'

'We should talk about suicide out loud,' she said.

Meryl Streep cheered, pointed and shouted 'Yes! Yes! Yes!' as Patricia Arquette ended her Oscar acceptance speech with a call for wage equality for women

Meryl Streep and Jennifer Lopez shared a selfie at the Oscars. They sat beside each other during the ceremony and shared in their approval of Arquette's speech

ACADEMY AWARDS 2015: FULL LIST OF NOMINATIONS Best Picture Birdman - WINNER American Sniper Boyhood The Grand Budapest Hotel The Imitation Game Selma The Theory of Everything Whiplash Best Director Alexandro G. Iñárritu, Birdman - WINNER Richard Linklater, Boyhood Bennett Miller, Foxcatcher Wes Anderson, The Grand Budapest Hotel Morten Tyldum, The Imitation Game Best Actor Eddie Redmayne, The Theory of Everything - WINNER Steve Carell, Foxcatcher Bradley Cooper, American Sniper Benedict Cumberbatch, The Imitation Game Michael Keaton, Birdman Best Actress Julianne Moore, Still Alice - WINNER Marion Cotillard, Two Days One Night Felicity Jones, The Theory of Everything Rosamund Pike, Gone Girl Reese Witherspoon, Wild Best Supporting Actor J.K. Simmons, Whiplash - WINNER Robert Duvall, The Judge Ethan Hawke, Boyhood Edward Norton, Birdman Mark Ruffalo, Foxcatcher Best Supporting Actress Patricia Arquette, Boyhood - WINNER Laura Dern, Wild Keira Knightley, The Imitation Game Emma Stone, Birdman Meryl Streep, Into the Woods Best Cinematography Birdman – Emmanuel Lubezki - WINNER The Grand Budapest Hotel – Robert Yeoman Ida – Lukasz Zal & Ryszard Lenczewski Mr. Turner – Dick Pope Unbroken – Roger Deakin Best Foreign Language Film Ida - WINNER Leviathan Tangerines Timbuktu Wild Tales Best Adapted Screenplay The Imitation Game - WINNER American Sniper Inherent Vice The Theory of Everything Whiplash Best Original Screenplay Birdman - WINNER Boyhood Foxcatcher The Grand Budapest Hotel Nightcrawler Best Makeup and Hairstyling The Grand Budapest Hotel - WINNER Foxcatcher Guardians of the Galaxy Best Original Score The Grand Budapest Hotel - WINNER The Imitation Game Interstellar Mr. Turner The Theory of Everything Best Original Song 'Glory,' Selma - WINNER 'Lost Stars,' Begin Again 'Everything is Awesome,' The LEGO Movie 'Grateful,' Beyond the Lights 'I'm Not Gonna Miss You,' Glen Campbell…I'll Be Me Best Animated Feature Big Hero 6 - WINNER The Boxtrolls How to Train Your Dragon 2 Song of the Sea The Tale of Princess Kaguya Best Documentary—Short Crisis Hotline: Veterans Press 1 - WINNER Joanna Our Curse The Reaper White Earth Best Film Editing Whiplash - WINNER American Sniper Boyhood The Grand Budapest Hotel The Imitation Game Best Production Design The Grand Budapest Hotel - WINNER The Imitation Game Interstellar Into the Woods Mr. Turner Best Animated Short Feast - WINNER The Bigger Picture The Dam Keeper Feast Me and My Moulton A Single Life Best Live Action Short The Phone Call - WINNER Aya Boogaloo and Graham Butter Lamp Parvaneh Best Sound Editing American Sniper - WINNER Birdman The Hobbit: The Battle of the Five Armies Interstellar Unbroken Best Sound Mixing Whiplash - WINNER American Sniper Birdman Interstellar Unbroken Best Visual Effects Interstellar - WINNER Captain America: The Winter Soldier Dawn of the Planet of the Apes Guardians of the Galaxy X-Men: Days of Future Past Best Documentary — Feature Citizenfour - WINNER Finding Vivien Maier Last Days of Vietnam The Salt of the Earth Virunga Best Costume Design The Grand Budapest Hotel - WINNER Inherent Vice Into the Woods Maleficent Mr. Turner Advertisement

Backstage, Patricia Arquette again spoke passionately about women deserving equal pay.

'It's amazing, but it is time for us. It is time for women,' she said. 'Equal means equal. And the truth is, the older women get, the less money they make.

'The more children ‑ the highest percentage of children living in poverty are female‑headed households.'

We don't have equal rights for women in America because when they wrote the Constitution, they didn't intend it for women. Patricia Arquette

'And it's inexcusable that we go around the world and we talk about equal rights for women in other countries and we don't have equal rights for women in America and we don't because when they wrote the Constitution, they didn't intend it for women.

'So, the truth is, even though we sort of feel like we have equal rights in America, right under the surface, there are huge issues that are applied that really do affect women.

'And it's time for all the women in America and all the men that love women, and all the gay people, and all the people of color that we've all fought for to fight for us now.'

The strong reaction from Meryl Streep, who has been a prominent advocate for eliminating the pay gap, should come as little surprise to anyone versed on the earnings of men versus those of women in Hollywood or any industry.

Between June 2012 and June 2013, Hollywood's ten highest paid actresses earned earned $181 million collectively, reported Variety.

The industry's ten top-earning men, on the other hand, earned $465 million.

Valerie Jarrett, adviser to President Barack Obama, cheered Arquette on Twitter.

'Thx for using your speech to advocate for EqualPay and for understanding that when women succeed, America succeeds,' Jarrett wrote

ARQUETTE BACKSTAGE ON THE 'MANI-CAM' AND WHY SHE SPOKE OUT Newly-minted Oscar winner Patricia Arquette continued to speak her mind backstage after her rousing speech, telling members of the press: I'm wearing a dress my best friend designed we've been best friends since we were 7 and 8-years-old and she was the first person to ask me what do you want to be when you grow up? I said I want to be and actor, I said what do you want to be? and she said I want to be in fashion and she became a fashion designer and she designed by gown so it's like wearing love. We created an organization givelove.org. And instead of getting a manicure this morning for the dreaded mani-cam I ended up trying to pull pictures because we started a sweepstake for charity to do ecological sanitation of the world. And when I saw Harry Belafonte's picture up there it reminded me of my mom who was an equal rights activist, she worked for civil rights and this is who I am this is the whole of who I am, I love my business, I love acting and I love being a human being and I want to help. I never saw this moment of me winning an Academy award, I never even thought id be nominated and I was OK with that, but you know what I did see? I saw many things that have come true in my life and one of those things was helping thousands and thousands of people. And I have and I will and I will help millions of people. Arquette said she's helped thousands of people and she vowed, 'I will help millions of people.' Arquette became the first member of her acting family to win an Academy Award. She had already claimed trophies from the Golden Globes, Screen Actors Guild, Independent Spirit Awards and BAFTA for her role. Advertisement

Arquette was not alone in her mission to use the night's high profile to shine a light on women's issues.

Her fellow nominee Reese Witherspoon continued the #AskHerMore trend from the Golden Globes with a demand for more important questions on the red carpet.

'This is a movement to say we're more than just our dresses,' Witherspoon told Robin Roberts. 'There are 44 nominees this year that are women and we are so happy to be here and talk about the work that we've done. It's hard being a woman in Hollywood, or any industry.'

Arquette plays the mother of Ellar Coltrane's Mason in Richard Linklater's Boyhood, a sweeping look at a boy's life, filmed over 12 years.

Arquette became the first member of her acting family to win an Academy Award. She had already claimed trophies from the Golden Globes, Screen Actors Guild, Independent Spirit Awards and BAFTA for her role.

Her father Lewis Arquette was an actor, her grandfather Cliff Arquette was a comedian, and her siblings, including sister Rosanna, have worked in show business.

Arquette's next project is a return to the small screen. She stars in the new series 'CSI: Cyber,' debuting in March on CBS.

Also nominated were Laura Dern in 'Wild'; Keira Knightley in 'The Imitation Game'; Stone in 'Birdman'; and Streep for 'Into the Woods.'

'This is a movement to say we're more than just our dresses': Best actress nominee Reese Witherspoon also used the Oscars to give voice to women who feel like second class citizens in Hollywood and made her opinions known while chatting with Robin Roberts on the red carpet