Nadia Eweida, 55, had refused to return to work since her employers told her last month that she could not wear the necklace to work.

The airline said that she had been offered a non-uniformed job where she could wear a cross, but Miss Eweida had turned this down.

BA continued to insist that if she wanted to carry on working in the check-in area at Heathrow, she would not be allowed to wear a cross.

BA has said that there is no ban on religious jewellery, but it has to be hidden from view. The Archbishop of York, Dr John Sentamu, appealed yesterday for the airline to reconsider its decision, describing it as “a nonsense based on flawed reasoning”.

“The basis for the decision should not be ‘practicality’, as BA suggests in its statement, but rather whether it impacts on Nadia’s ability to do her job. It is clear that Nadia’s cross does not form an impediment to her ability to carry out her duties at the check-in counter.

“Under BA’s reasoning, an employee who turned up to work wearing a three-foot-long cross must be allowed to wear it, because to hide such a cross under their uniform would be impractical. Yet in Nadia’s case a cross of less than three inches is deemed a problem.”

Miss Eweida, of Twickenham, southwest London, said that she had worn the cross throughout her seven years with BA. “They are treating me unfairly and discriminating against me on religious grounds. Sikhs and Muslims are allowed to wear certain clothes, but my small cross is not acceptable,” she said.

She added that she did not want to hide the cross because “Jesus has to be glorified”. She added: “I am not politically motivated or minded, I just follow the Biblical truth.” She was flown to America by a television company after her case became known last month, where she said she received “overwhelming support”.

Peter Hain, the Northern Ireland Secretary, said recently that BA was “loopy” to ban an employee from wearing a cross.

BA said in a statement yesterday: “British Airways has 34,000 uniformed staff, all of whom know they must abide by our uniform policy.

“The policy does not ban staff from wearing a cross. It lays down that personal items of jewellery, including crosses, may be worn — but underneath the uniform. Other airlines have the same policy.

“Our uniformed staff, many thousands of whom are Christian, have happily accepted the policy for years. The policy recognises that it is not practical for some religious symbols — such as turbans and hijabs — to be worn underneath the uniform. This is purely a question of practicality. There is no discrimination between faiths whatsoever. British Airways is a worldwide company operating in 90 countries. We have staff and customers of all faiths and none. The uniform policy reflects the need to present a professional and consistent image wherever we operate.

“Nadia was told today that her grievance appeal against the uniform policy had been unsuccessful. We understand she intends to exercise her right to a second appeal.”

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