British Airways check-in worker Nadia Eweida faces further disciplinary action for daring to speaking out about her fight to wear her cross, it emerged.
The devout Christian was hauled before senior managers to hear her appeal against BA's dress code banning crosses to work.
But during the meeting Miss Eweida was warned that talking publicly about her case also breached company rules.
BA's employment book states workers must seek permisson from the company before speaking about the airline.
The move brought further condemnation over BA's behaviour and escalated the row over the right of Christians to express their belief by wearing crosses to work.
Her union, the TGWU, insisted Miss Eweida had a right to speak out and was blowing the whistle on an injustice, while her MP condemned any attempt to intimidate her.
Miss Eweida, 55, of Twickenham, south-west London, is a Coptic Christian with an Egyptian background.
She was forced to take unpaid leave after refusing to remove the tiny cross on her necklace nearly four weeks ago. She is waiting to hear whether her appeal has been successful.
If BA uphold their ruling she is planning to sue the airline for religious discrimination because the airline allows Muslims and Sikhs to wear headscarves, turbans and bangles.
Her case, revealed by the Daily Mail, attracted widespread attention and the backing of a string of MPs and Ministers including Communities Secretary Ruth Kelly, Northern Ireland Secretary Peter Hain, and Conservative former Minister Ann Widdecombe.
But BA said speaking to newspapers and appearing on television without permission was banned.
A friend of Miss Eweida said: "Nadia has been warned by BA that by publicising her case to the British people she was in breach of company rules.
"It was implied that there could be adverse consequences. But she believes that she has done nothing wrong and that God is more important than British Airways' company policy.
"She says that Jesus was not a wimp and she does not intend to be a wimp."
Miss Eweida's MP Vince Cable, LibDem deputy leader, said: "If there is any suggestion whatever that she is going to be sanctioned for having spoken about this to the media, it would put British Airways in an even worse light than they are at the moment.
"They have behaved badly and if there is any attempt to intimidate employees into silence this would leave what is left of their reputation in shreds."
Miss Widdecombe, who has torn up her BA executive card and called for Christians to boycott BA in protest, said: "It seems to me as if BA are simply looking for pretexts. She has a right to speak out about this."
More than 300 BA workers have now signed a petition in support of Miss Eweida.
The airline's staff are planning a 'Crucifix Day' protest in solidarity, with air crews and ground staff wearing crosses on lapel badges and neck chains.
A BA spokesman said: "We do have a policy that states that employees should seek permission before they speak to the media. We cannot go into this individual case pending the appeal."