The firm, which represents the Obamas and a slew of other high-profile individuals, will offer the couple a source of income as they branch out on their own.
"They have no plans to do any speaking engagements about the royal family," the source notes, adding that there have been concerns that any further talk of their royal lives could bring "further discomfort" within the royal family.
The source says the couple is "firmly committed to social issues the world is facing now, including racial justice, gender equity and mental health."
ET has also learned that any new speaking engagements would be used to further the conversation on these issues of importance. They are expected to participate in keynote speeches, trade events and community forums to "further their philanthropic goals."
Harry and Meghan are “signed solely with Harry Walker for speaking engagements and not with any other agencies for other purposes," the source adds.
The news comes just a day after the couple visited Homeboy Industries, a community social justice organization working to improve the lives of formerly incarcerated and previously gang-involved people in L.A.
This video is unavailable because we were unable to load a message from our sponsors.
If you are using ad-blocking software, please disable it and reload the page.
Meghan Markle Gives Emotional Graduation Speech to Her Alma Mater Amid Protests
While there, Meghan and Harry joined the Homies working in the Homeboy Bakery and Homegirl Café for a session of cooking and conversation. Together they prepared food for the #FeedHOPE program, which employs Homeboy participants to provide meals to food-insecure seniors and youth across L.A. during the COVID-19 pandemic.
The couple has been finding ways to give back and speak out against injustices since making Los Angeles their new home. After the former Suits actress delivered an impassioned speech amid the ongoing protests in the wake of George Floyd's death -- which made her the first royal to speak out in support of Black Lives Matter -- she and Harry got more involved in the movement.
"The Black Lives Matter movement matters to Meghan and it matters to Harry. And I understand that this is going to be an area where we're going to see the couple doing a lot more work and taking a lot more interest," royal expert Katie Nicholl recently told ET. "They've been very busy with the COVID efforts, particularly how it's impacting on their charities. And their focus is now, I'm told, shifting onto this movement -- Black Lives Matter is something that really resonates with both of them."
Additionally, earlier this month, a source told ET that Meghan and Harry's relationship is "stronger than ever," and noted that they used their time in quarantine to be thoughtful and strategic about the type of work and projects they want to be involved in moving forward.