According to the Los Angeles Times, Morgan Creek Productions have teamed up with Skee.TV on the promotion, which asks hopefuls to upload a five-minute audition video, and is open until the end of April.
"This audition process is a great example of utilising today's ever-evolving technology to reach fans and actors around the world to pay homage to a hip-hop legend," Skee.TV founder DJ Skee said in a statement.
The applicants must perform a prepared monologue specified by the film's producers, as well as a one-minute performance of a chosen Tupac song.
Shakur was frequently the centre of controversy during his career as a successful rapper, and has since inspired countless conspiracy theories following his unsolved murder in 1996.
In August last year, it was confirmed that Ali screenwriters Stephen J. Rivele and Chris Wilkinson would pen the film's script, following the announcement that Brooklyn's Finest director Antoine Fuqua would helm the project.
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