Federal Labor believes senior members of the coalition are under-stating the struggle many gay and lesbian people are going through especially as the same-sex marriage postal survey gets under way.
Mental health advocates have raised concerns about the potential negative impact of the survey debate.
Asked about the concern, stood-aside minister Matt Canavan said it was time to "grow a spine".
"I mean, let's stop being delicate little flowers and have a proper debate," he told Sky News on Monday, a day ahead of the survey forms being posted.
Labor frontbencher Chris Bowen said such comments were "very unfortunate".
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"There are young people in particular who are struggling with coming out, who are struggling with this debate," he said.
Labor mental health spokeswoman Julie Collins said there were studies showing young gay, lesbian, bisexual and transgender people were six times more likely to die from suicide.
"There is no room for any person to be given a license to air hateful, ignorant or unsubstantiated views that may cause harm," she said.
"This includes Senator Canavan."
Earlier, Deputy Prime Minister Barnaby Joyce - who is advocating a "no" vote - urged all involved in the debate to turn down the volume, especially those in the "yes" camp.
"I just don't want people standing on the corner yelling at me, telling me if I don't agree with them then I'm somehow less than human," he said.
"Get out of my face."
Senator Canavan said it was wrong for the "yes" case advocates to accuse the "no" camp of being "bigots".
Ahead of the survey forms being posted, Labor and the coalition are in talks over protections against vilification in campaign material.
Labor has asked the government to include a provision that would ban hate speech.
"It looks at this stage like the government's prepared to agree to that," shadow attorney-general Mark Dreyfus said.
But Liberal senator James Paterson said it was genuinely not possible for the government to regulate the content of people's communications during the postal survey.
The senator targeted calls for ensuring that the information provided in campaign material be true.
"Truth in advertising is almost certainly unconstitutional and a violation of the implied right to political communication," he told reporters in Canberra on Monday.
"I think we should be very careful about going further than we normally do for normal elections."
The government is aiming to have the protections legislated by the end of the week.
