Celebrity Big Brother housemates Shilpa Shetty and Jade Goody have both denied the rows they have had were racist.
Shetty, 31, is an award-winning Bollywood actress
The Bollywood actress told another housemate: "When I actually thought about it, I know it's not a racist thing...people say things in anger."
Meanwhile, in the Diary Room, Goody said: "What I said about her was not meant in a racial way. If it's offended any Indians out there I apologise."
Carphone Warehouse has suspended its sponsorship of the show over the row.
On Thursday night, Shetty told former Steps star Ian "H" Watkins that the behaviour of her housemates may not be racist.
She added: "I thought about it for a long time. It's not racist.
"She tries to challenge me. She tries to challenge my beliefs."
Later, while Goody was in the Diary Room, Big Brother asked her about the conversation with Danielle Lloyd, in which she referred to the actress as Shilpa "Poppadom".
Goody, who first found fame on the non-celebrity version of Big Brother, responded: "She is Indian, [I was] thinking of an Indian name and [the] only thing I could think of was Indian food.
"Wasn't racial at all. It was not to offend any Indian out there.
"Everyone knows I don't like her. She don't like me. What I said about her was not meant in a racial way - it's not acceptable if done in that way."
Carphone Warehouse said its sponsorship would be removed from the current series "with immediate effect".
Chief executive Charles Dunstone said in a statement: "Our concern has rapidly mounted about the broadcast behaviour of individuals within the Big Brother house."
The company has paid out about £3m in sponsorship so far this series.
But Channel 4 chief executive Andy Duncan said at a press conference it would not be pulling the programme.
Government Chief Whip Jacqui Smith waded into the furore, urging people not to watch Big Brother because of what she described as "racist bullying".
Goody joined the house with her mother and boyfriend Jack Tweed
In the strongest condemnation of the show by a minister so far, she said the behaviour had been totally "unacceptable".
Ms Smith also attacked the programme-makers, saying that the editing had been wrong and that it was "shameful to make money and publicity out of that sort of thing".
A record 30,000 complaints have been made over alleged racist remarks towards Shetty.
Three of her fellow housemates have been accused of racist behaviour, with Goody, 25, receiving the brunt of public criticism.
On Wednesday's show, Shetty told housemate Cleo Rocos she feared she was being targeted because of her race.
Questioned about comments
Mr Duncan said Channel 4 were constantly monitoring the show and that some of the contestants had been spoken to in the Big Brother diary room about how their comments might be perceived.
Shetty and Goody will go head-to-head in the forthcoming Celebrity Big Brother evictions on Friday, with Goody rated by bookmakers as the overwhelming favourite to be evicted.
The Perfume Shop chain has also decided to withdraw sales of Goody's perfume from its shelves following the controversy.
However, a spokeswoman for Goody has denied she is a racist.
Goody's mother Jackiey Budden, who was also a contestant on the show but was evicted last week, said: "Jade has never been racist, she is mixed race herself and suffered racist abuse as a youngster."
The Carphone Warehouse decision follows media watchdog Ofcom's demand that Channel 4 must respond to complaints about "racist" comments.
More than 30,000 complaints have been made so far to media regulator Ofcom and 3,000 directly to Channel 4.
However, the explosion of media coverage has seen audience figures rise, with 3.5 million viewers tuning in on Monday, 4.5 million on Tuesday and 5.2 million on Wednesday - equalling the highest figure for this series since the live launch.