"Whilst these complainants have not raised the allegations directly with our show producers or parent company Banijay UK, we feel that it is appropriate to conduct an immediate, external review to fully and impartially investigate," Banijay's statement continued.
"While this review is under way, Gregg Wallace will be stepping away from his role on MasterChef and is committed to fully co-operating throughout the process.
"Banijay UK's duty of care to staff is always a priority and our expectations regarding behaviour are made clear to both cast and crew on all productions, with multiple ways of raising concerns, including anonymously, clearly promoted on set.
"Whilst these are historical allegations, incidences brought to our attention where these expectations are not met, are thoroughly investigated and addressed appropriately."
Banijay's statement concluded by encouraging anyone who wanted to raise any issues or concerns to come forward.