The broadcaster and the watchdog Ofcom have received thousands of complaints about the treatment of Shetty, who has encountered a tirade of insults from the former house- mate Jackiey Budden, her daughter Jade Goody and, to a lesser extent, from the model Danielle Lloyd. The Labour MP Keith Vaz led the protests, tabling an early day motion in the Commons after members of his Leicester East contacted him. His motion calls on the programme: " To take action to remind housemates that racist behaviour is unacceptable."

He said: "Channel 4 has a duty to tell the housemates there are limits. It is totally unacceptable. We can be fun without being rude and insensitive to people about their ethnic origin."

Channel 4 said it would "take appropriate measures to reprimand such behaviour where necessary", but fell short of indicating it would communicate the unacceptability of racism to housemates. It has also defended its decision not to intervene in the group dynamics, insisting that it had to portray events accurately. Carphone Warehouse, which sponsors Big Brother for an estimated £3m per year, is reported to be reviewing its association with the programme.

The actress and comedian Meera Syal attacked Channel 4's "bland" response to the controversy, which has led thousands of people to complaining. Speaking on the BBC Asian Network, she said: "I certainly wouldn't have taken as much as Shilpa has taken. I'm just wondering if on their last series, for example, the Tourette's sufferer had been called a 'spaz' on a regular basis, whether they would have let that continue?"

By 9.30 this morning, Ofcom had received 13,000 complaints - the highest ever made about the show - and Channel 4 had fielded a further 2,000 e-mails and calls over the treatment of Shetty, who is also an Aids campaigner.

In Monday's episode, the former S-Club 7 singer Jo O'Meara said Indians were thin because they were always ill as a result of undercooking their food. She and Lloyd also complained that Shetty had touched other housemates' food with her hands. Lloyd said: "You don't know where those hands have been. " The abuse was started by Budden, who repeatedly referred to Shetty as "the Indian". Budden's behaviour prompted the departure of the film director Ken Russell, who branded her and her family "slum dwellers ".

Shetty, the first Indian contestant to appear on Celebrity Big Brother, was largely unknown in Britain until she appeared on the programme. But she is one of Bollywood's best-known actresses, and has been nominated for the Filmfare award four times.