Tanya Burr has said she's "100%" sure there's snobbery at work among those who say she was only cast in her debut theatre role because of her YouTube fame.

Tanya, who has a fashion and beauty YouTube channel with more than 3.7 million subscribers, will play the lead role in Judy Upton's 1990s-set play Confidence by Boundless Theatre at London's Southwark Playhouse.

In answer to a critic in theatre publication The Stage, who referred to it as "stunt casting", Tanya told 5 live's Nihal Arthanayake they "probably didn't know she has been studying theatre for years".