A Catholic charity has accused Facebook of acting like an "arbitrary censor" after its advert was pulled and restrictions imposed on its use of the social media platform.
The advert was posted by Aid to the Church in Need (ACN) and promoted a petition calling on the UK government and UN to do more to protect Christian and other minority faith women from sexual violence.
Facebook blocked the advert on 11 November and "severe restrictions" were then imposed on the charity's use of the platform for the following eight weeks, ACN said.
This included blocking its access to the Facebook-owned WhatsApp messenger platform.
ACN said the removal of the advert significantly affected the number of signatures it was able to attract to the petition.
The charity said that before the ban was imposed, the advert was seen by around 3,000 Facebook users a day, garnering an average of 400 signatures every day.
After the ban, the advert was seen by only around 280 Facebook users a day, with daily signatures falling to only 38.
The restrictions have now been lifted but ACN says no reason has been given by Facebook or its parent company, Meta, as to why access was limited in the first place despite numerous requests for clarification.
ACN UK national director, Neville Kyrke-Smith, welcomed the removal of restrictions but criticised Facebook's actions and accused the social media giant of "muzzling" debate on the platform.
He said: "We are delighted that after almost two months of trying to get Facebook to explain their actions and reverse their block – and a media push which attracted a lot of public outrage – they have finally lifted these excessive and crippling limitations on ACN's use of their platform and facilities.
"But by refusing to explain how they justify the ban, we are hard pressed to see this as anything more than arbitrary censorship – which was used to silence some of the world's most vulnerable women.
"Regrettably, this whole episode shows that Facebook thinks it has the right to censure without explanation and without any chance of redress – it is muzzling debates that are literally matters of life and death."
Facebook has been contacted for comment.