House of Commons leader Jack Straw has described the British Airways ban on staff wearing cross necklaces over their uniform as "wholly inexplicable".
Nadia Eweida refuses to wear her cross under her uniform
Mr Straw was asked by Labour MP Ian Austin whether there could be a debate on the treatment of Nadia Eweida, who lost an appeal against the ban.
Other items of religious significance, such as turbans or hijabs which cannot be hidden, can be worn under BA policy.
Mr Straw said it was inexplicable that crosses were not included.
Mr Austin said more than 100 MPs had signed parliamentary motions asking BA to re-think the ban, and constituents and the Church of England were also upset by it.
Mr Straw, in the Commons on Thursday, said: "I speak personally on this - and the government doesn't have a particular government position - I share his concerns about this.
"I have a great admiration for British Airways as an airline, but I find their position on this quite inexplicable."
He added: "I have strongly supported the right of Sikhs to wear turbans both in private companies and the police service and the Army, [and] I have strongly supported the right of women of the Muslim faith to wear the hijab...in all circumstances.
"I therefore find the ban on wearing a cross or indeed a Star of David in equivalent circumstances wholly inexplicable."
Nadia Eweida, 55, of Twickenham, London, has been on unpaid leave from Heathrow since her bosses said she could not wear her cross over her uniform at the check-in counter.
She lost her appeal against BA's decision, but has the opportunity for a second appeal.
BA said last week: "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."