Flyers have been put up in Cardiff urging Muslims not to vote as democracy "violates the right of Allah".
The notices were put up on lamp-posts and bus stops on Friday morning in Grangetown - an area with a significant Muslim population.
Many have been ripped off and Cardiff council said a cleaning team will remove any remaining ones.
A trustee for the Muslim Council of Wales said the posters did not reflect views of the majority of Muslims.
The flyers stated: "Democracy is a system whereby man violates the right of Allah and decides what is permissible or impermissible for mankind, based solely on their whims and desires.
"Islam is the only real, working solution for the UK. It is a comprehensive system of governance where the laws of Allah are implemented and justice is observed."
Akmal Hanuk, a trustee at the Muslim Council of Wales, said: "It is not representing the views of the majority of Muslims. I think the majority of Muslims want to vote and will.
"From a Muslim Council of Wales perspective, we encourage them to vote and to have a say in the democratic system."
A Cardiff council spokesman said it was already working to removed the flyers.
"Priority is given to fly posting that can cause offence or is religiously motivated," said an official.