Comedians Catherine Tate, Matt Lucas and David Walliams have called in their lawyers after a Christian group used their catchphrases on its posters.
Tate (l) and Lucas (r) are two of the biggest names in British comedy
Christian Publishing and Outreach (CPO) featured Tate's "Am I bovvered?" remark and Little Britain's "Yeah, I know!" in a campaign aimed at young people.
Representatives for the stars confirmed solicitors would be contacting CPO.
CPO admitted it had not sought permission to use the material, and said the posters had been withdrawn.
The campaign also featured Tate's "How very dare you" and the "Yeah but no but yeah" mantra of Little Britain's Vicky Pollard.
Under the catchphrases, each poster featured a quote from the Bible.
Tate's production company Tiger Aspect confirmed it had instructed solicitors to act on her behalf.
Lucas and Walliams' management said their legal representatives had been in contact with the evangelical Christian organisation.
Before the brightly-coloured posters were withdrawn, CPO had been selling them to churches for £25 a set.