Sydney -

The Australian Christian Lobby said on Thursday that Prime Minister Julia Gillard's boycott of its national conference over a comment on gay sex by its leader was a blow to free speech.

Gillard cancelled plans to attend after lobby boss Jim Wallace declared that gay sex was a bigger health hazard than smoking cigarettes.

“This is a victory for the relentless campaign of demonization against anyone who would challenge the gay activists' agenda in the public square,” the lobby declared on its website.

Gillard, announcing her boycott, said: “To compare the health effects of smoking cigarettes with the many struggles gay and lesbian Australians endure in contemporary society is heartless and wrong.” - Sapa-dpa