THE Church of Scientology is threatening to sue a volunteer organisation for publishing a brochure it claims labels the religion a ''cult''.

But the Cult Information and Family Support (CIFS) group, which helps victims of cults and their families, refuses to bow to the demands of the Scientologists, saying they will continue their ''humanitarian support work''.

The brochure advertises the support group's national conference in Brisbane next month and quotes one of the speakers, Senator Nick Xenophon, from a speech in Parliament in 2009 in which he labelled Scientology a criminal organisation.

The brochure contains allegations from that speech that members of Scientology had experienced ''blackmail, torture and violence, labour camps and forced imprisonment and coerced abortions''.

But in a legal letter, the Scientology lawyer, Kevin Rodgers, of Sydney firm Brock Partners, said the brochure was ''grossly defamatory of [the Church of Scientology], its officers and parishioners''.