Big Brother has given one of the TV reality programme's two Welsh-speaking housemates a telling-off for talking in his native language.
School head boy Glyn Wise says he is a "future model"
Glyn Wise, 18, a part-time lifeguard from Blaenau Ffestiniog, is among 14 housemates in the Channel 4 show.
He was told by the voice of Big Brother that using Welsh with ex-Miss Wales Imogen Thomas, of Llanelli, was speaking "in code".
But a Big Brother spokeswoman denied there was a ban on speaking Welsh.
Glyn was called to the diary room, where contestants regularly go to speak to Big Brother, to pick up some batteries.
But the authoritarian voice took the opportunity to tell him off for speaking Welsh.
"But Welsh is British," countered sixth-form student Glyn.
Big Brother replied: "It's not English, and could be considered to be talking in code."
However, the programme denied there was a Welsh ban in the house.
A Big Brother spokeswoman said: "Housemates are free to talk in any established language of their choosing.
"However, any discussion that is deemed to be against Big Brother rules may be punishable. Big Brother is multi-lingual and always listening."
She added that any Welsh spoken on the programme would be translated via subtitling.
A spokesman for the Welsh Language Society said: "Are we moving towards a state where 'big brother' is watching over us and deciding what language we can and cannot speak?"
The campaign group said it had complained to Channel 4, Ofcom and S4C - the Welsh fourth channel which also shows the programme.
"We are especially disappointed that S4C has chosen to broadcast this show, given that the whole point of S4C is to broadcast and promote the Welsh," said the spokesman.
Glyn had said in his profile for the programme that he feels strongly all Welsh people should speak the language.
He said he entered the house to show off his "sexy body" to millions, and that the fact that he is head boy at Ysgol Dyffryn Conwy in Llanrwst, proved he was "very popular".
Former Miss Wales, Imogen, says she is "sexy, edgy and confident"
He also claims he was voted the "sexiest lifeguard in north Wales".
His fellow Welsh-speaker Imogen is a bar hostess who was Miss Wales in 2003, and has a BSc degree in health studies and psychology.
Imogen said she entered the house to "show the nation what I'm like".
She added: "I want to be free from the outside world, that would be great as I would have no worries."
Psychologist Cynthia McVeigh believed the two Welsh-speakers will have an advantage over their fellow housemates.
'Sense of comfort'
"It's not just the dimension of them being able to talk about other contestants while they're there, but also that this could be thoroughly irritating to the other contestants," she said.
"It's really terrific that they have this language which is fluently spoken. They can talk to each other, and nobody else will have a clue."
Ms McVeigh said it would also "give them a sense of comfort, and a little bit of additional social support that nobody else will have".
But Alkarim Jivani, Time Out's TV editor said their second language could make the other contestants "pick on" them.
"They'll be the first people to be nominated, but then the question is having been nominated, will they be evicted?"
But Mr Jivani believed their presence on the show could boost the Welsh language.
"Big Brother has so much influence on fashions among young people, it could have a really interesting impact on the way young people perceive the Welsh language, and also how many people want to learn it," he said.