Activists responsible for bringing Melbourne to a standstill earlier this year have been warned they could be stripped of their charitable status for promoting unlawful activity.

Charities Minister Zed Seselja said he had "serious concerns" that activist organisation Aussie Farms could undermine public trust in established charities like the St Vincent de Paul Society and has referred Aussie Farms to Charities Commissioner Gary Johns who has the power to strip non government organisations of their special tax status.

Vegan protesters in Melbourne earlier this year. Credit:Zach Hope

"I support charities advocating for causes they believe in but when groups are promoting unlawful activity, they are stepping over the line," Senator Seselja told The Sydney Morning Herald and The Age.

"Charities like Vinnies [the St Vincent de Paul Society] and the Salvos [Salvation Army] and many others do amazing work selflessly caring for those in need. It is offensive they are given the same legal status as groups inciting criminal activity."