The 23-year-old actor-turned-parish councillor from Braintree, Essex, had previously received warnings for unacceptable language.
It’s understood that most were not broadcast. However, Monday’s episode showed Gilbert being reprimanded by Big Brother for imitating another housemate during a game of Truth or Dare.
Big Brother referred to one moment in the game when he was asked about his least favourite qualities of other housemates.
“You then went on to mimic Sam using both noises that mocked the way Sam talks and body language that included limp wrists,” Big Brother said.
“Do you understand how both your language and behaviour could be offensive to Sam, your housemates and the viewing public?”
Gilbert replied: “We did have a conversation about this, I have apologised, I don’t want to make anyone feel like that.”
Big Brother then confirmed it was issuing him with a formal warning, and said rules regarding language and behaviour are explained to all housemates before entering.
ITV has also said housemates receive training in respect, dignity and inclusion.
Gilbert was one of the contestants who was up for eviction this week, alongside Elsa, Cameron and Richard.
Friday’s eviction will continue as planned despite his removal, ITV said.