Scott Morrison has rejected suggestions an under-fire Liberal candidate for the Victorian seat of Chisholm is homophobic.
Gladys Liu is under pressure for describing LGBTI issues as "ridiculous rubbish" and arguing same-sex marriage is "against normal practice".
Mr Morrison has backed Ms Liu's claims that she was simply reflecting the views of her community while making the anti-gay remarks in 2016.
The prime minister said Ms Liu had led an "amazing Australian life" and he was proud to launch her campaign.
"As she said at the time when she was campaigning for the previous Liberal candidate, and now current member in Chisholm, she was simply saying that these were the views of that community," he said on Tuesday.
Veteran Liberal senator Arthur Sinodinos said Ms Liu made a "rookie error" and should not have made the remarks, even if she was repeating the views of people in her community.
"That was a rookie error," he told ABC News.
"I think all of us know where we stand on these issues. We live in an inclusive society. We need to be continually out there seeking to bring people together."
In recent days, Ms Liu has claimed stories about her comments were "fake news" and not representative of her views.
Opposition Leader Bill Shorten said the prime minister's handling of her comments would be a test of his leadership.
"He needs to make up his mind on a couple of questions," Mr Shorten told reporters in Adelaide.
"Whether he wants as a candidate for the Liberal Party someone who said such hurtful things about her fellow Australians.
"And two, whether he wants as a candidate for the Liberal Party someone who stood in front of the media and said it didn't happen when clearly it did."