Bravo; Chad Kirkland/Bravo/NBCU Photo Bank/Getty
Nguyen, 44, is currently facing backlash for racially insensitive social media posts of hers that have resurfaced. Some of the now-deleted Facebook posts were critical of the Black Lives Matter movement and the controversial death of George Floyd, a man who was killed in May 2020 by ex-police officer Derek Chauvin.
When the news first broke, Marks, 49, seemingly addressed it on Wednesday by tweeting: "Vile." On Friday, she shared a quote from Martin Luther King Jr. and urged others to "speak out against what is wrong and amplify those that are not being heard."
"There is no room in this world for hatred. We are all human beings and deserve the same treatment of respect and dignity," she wrote on Twitter. "Negative commentary rooted in prejudice regarding one's race, ethnicity, religion, sexuality or gender is vile and should never be tolerated."
"Educate if it comes from a lack of knowledge and condemn if it comes from a place of hatred," she added. "I pray to see this world without prejudice."
Marks has since chosen to directly speak on the controversy, sharing a lengthy message on Twitter Sunday.
"Since it was not perfectly clear in my previous tweet and I can now speak out in more depth, I am sickened by my co-worker's racist and prejudicial posts that recently surfaced," she wrote. "I do not stand behind or support these posts in any way, shape, or form."
"I stand with and support the communities affected and targeted by this," she continued. "I am deeply disturbed and outraged by her actions. Black Lives Matter."
Concluding her statement, Marks asked that fans remain patient in this situation.
"You will see repercussions," she wrote. "As difficult as it is, give things a moment to come to light. Know that I do not support this behavior in anyway and will continue to use my platform to speak out against it."
Nguyen recently broke her silence by acknowledging and apologizing for her controversial posts.
"At the time, I thought I was speaking out against violence, but I have since learned how offensive and hurtful my words were," the reality star wrote on Wednesday. "It's why I deactivated that account more than a year ago and why I continue to try to learn about perspectives different from my own. I regret those posts and am sincerely sorry for the pain they caused."
Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.
Marks isn't the only RHOSLC costar of Nguyen's to publicly condemn her actions. Jen Shah — whose husband, Sharrieff Shah, and sons, Omar and Sharrieff Jr., are Black — said she "must now stand up" on her family's behalf.
"I am deeply offended by the racially insensitive posts and comments," Jen, 48, wrote on Instagram Thursday. "It was infuriating to see her like and repost comments that made a mockery of and showed complete apathy toward those killed marching to bring awareness to the deep-seeded social justice issues that plague our country."
Jen added that she's "equally disappointed by the disingenuous apology" that Nguyen issued. "Needless to say, we have some real s— to talk about," she concluded.
Lisa Barlow — a longtime friend of Nguyen's — also addressed the controversy, saying her "heart hurts for those hurting."
"My heart is so heavy right now. I feel true hurt and disappointment by the posts that surfaced," she wrote on Instagram. "I do NOT condone, nor am I aligned with them. The posts were harmful and hurtful to a community I love."
"Working for change is constant; it's something that I personally work towards daily," she continued. "Through action is where we all have the most impact and where we can have change that lasts. I want to be a support and be a proponent for change and improvement."
On Monday, Andy Cohen confirmed on an episode of his SiriusXM show, "Radio Andy" that "there are many serious discussions happening right now" regarding Nguyen's controversy and "it will be addressed very soon."
"People were very upset about the lack of discussion on last night's episode relating to Jennie's disgusting and upsetting posts, and I've also seen all the tweets wanting to know what's being done about those posts," he said. "I just want to say, in case anyone doesn't realize it, that there are many serious discussions happening right now about everything — about everything. And I can't address the situation right now, but it will be addressed very soon, and thank you for your patience. And the posts were very upsetting, rightfully, and disgusting."
RELATED VIDEO: RHOSLC's Mary Cosby Claps Backs After Her Religion Is Questioned: 'I Worship the God in Me'
"It is insulting to our Asian culture to call me that, and it comes across as racist," Nguyen said in a confessional. "And it's shocking cause Mary should be more educated and understand it's not appropriate to say stuff like that."
That same episode, Nguyen called out Cosby while at a gathering with the other housewives: "You're an adult, take some responsibility. Right now, there is a lot of Asian hate. Take responsibility for your words."
Offscreen, Cosby said on Twitter her remark was "coming from a place of a compliment."