The group have been accused of increasing stigma around suicide by mental health charities.

An Australian anti-gay group opposed to same-sex marriage has been criticised by mental health bodies after sharing an image of a distressed women with a rainbow noose around her neck.

The tweet – posted by the Marriage Alliance – claims that marriage reform would lead to people who oppose same-sex marriage being bullied in the workplace.

Mental health charities BeyondBlue and Suicide Prevention Australia were quick to respond to the tweet, suggesting the image would only increase existing stigma around suicide.

“We’re advocating strongly in this space to reduce stigma & harmful messages around suicide like this,” BeyondBlue wrote.

The issue was later raised by Labor MP Tim Watts who described the tweet as “crap” in a speech to parliament.

Watts went on to criticise the government policy of a plebiscite on same-sex marriage, saying the photoshopped noose image was an example of a tax-payer funded campaign against marriage reform.

“[Prime minister] Malcolm Turnbull will be writing cheques to the types of groups who photoshop rainbow nooses over stock photos,” Watts said.

Watch his full speech below:

Australian MPs have threatened to call for the planned public vote on same-sex marriage to be scrapped, over criticisms of the process.

Despite an overwhelming majority of the Australian public supporting equal marriage and a majority of MPs in favour, the current Liberal-led Coalition government refuses to put the issue to a free Parliamentary vote due to deep political divisions.

Instead, the government is planing a marriage plebiscite (public vote) after the election in 2017 – a measure which has been derided as costly, bureaucratic and pointless, given anti-gay marriage MPs insist they will not consider the vote binding either way.