Ms Lankston continued: "This documentary has been made in collaboration with a very important charity that is based out of Africa.
"Harry and Meghan both have a connection to this charity.
"They went to Botswana back in 2017, all those years ago.
"They actually worked with the elephants there, they got to meet them up close and personally, they got to see what goes into caring for them."
The royal commentator added: "So this is a project that is actually very close to Meghan's heart.
"But it is important to note that she is doing a voice-over for Disney.
"I'm sure many royal fans will remember that viral clip of Prince Harry talking to the Disney head Bob Iger and saying to him 'my wife is very interested in doing a job with you, she's good at voiceovers' so it looks like Harry's strong-arming worked."
The Duchess of Sussex's new project will benefit Elephants Without Borders and was shot before she and husband Prince Harry made the decision to step down as senior members of the royal family.
"Elephant" looks at the story of African elephant Shani and her son Jomo as they journey across the Kalahari Desert.
The new doco will debut on April 3 on Disney+ along with a documentary about dolphins narrated by actress Natalie Portman.
The news comes after Meghan's nickname on the set of her former show Suits was revealed.
Royal commentator Omid Scobie spoke on Vice's Vice Versa: Meghan Markle Escaping The Crown podcast, Omid where he spilled the tea.
The Duchess, 38, who played the role of Rachel Zane on the legal drama between 2011 and 2017, was reportedly called 'Meghan gets s*** done' by her fellow cast members.