An agency which sells advertising to some of Britain's biggest cinema chains said it treats "all political or religious beliefs equally" amid a row about the banning of an advert featuring the Lord's Prayer.
Digital Cinema Media (DCM) defended its decision to keep the advert off-screen, saying some ads could cause offence to people of different faiths, political persuasions or those of no faith.
The London-based firm, which handles adverts for Odeon, Cineworld and Vue cinemas, responded as the Church of England (CoE) threatened legal action over the banning of the ad.
The advert, produced by JustPray.uk, shows the Lord's Prayer being recited by members of the public ranging from bodybuilders to children, and also features the Archbishop of Canterbury, the Most Rev Justin Welby.
The minute-long advert received clearance from the British Board of Film Classification and the Cinema Advertising Authority, but DCM has refused to show it.
In a statement, DCM said: "DCM has a policy of not accepting 'political or religious advertising' content for use in its cinemas.
"Some advertisements - unintentionally or otherwise - could cause offence to those of differing political persuasions, as well as to those of differing faiths and indeed of no faith.
"In this regard, DCM treats all political or religious beliefs equally."
Mr Welby said it is "extraordinary" that Britain's biggest cinema chains have banned the advertisement.
The CoE initially believed it had been approved and would be played before showings of Star Wars: The Force Awakens from December 18.
But they were later told that, due to a DCM policy not to run adverts which could potentially cause offence, the advert would not be shown.
When asked for a copy of that policy, the CoE was told that there was no formal policy document but that it had been agreed with DCM's members.
A formal policy now appears on DCM's website, stating: "To be approved, an advertisement must ... not in the reasonable opinion of DCM constitute political or religious advertising."
DCM did not immediately respond to reports that the document was only created last Friday - just two days before the Mail on Sunday revealed the ban.
Stephen Slack, the Church's chief legal adviser, has warned the ban could trigger legal action under the Equality Act, which bans commercial organisations from refusing services on religious grounds.
But Terry Sanderson, the president of the National Secular Society, accused the Church of being "arrogant" to imagine that it can "foist" its opinions on captive cinema audiences.